HV Battery State of Health (SoH) - what to ask before buying
Discussion
Does a SoH value between 70-100% actually matter in a 296? Does a value of 73% mean it’s slower than a car with a value of 93%? If not, what’s the issue?
I hope you guys are aware that these software derived SoH numbers are pretty random? I have occasionally looked at them in EVs I’ve had and they go up and down.
I hope you guys are aware that these software derived SoH numbers are pretty random? I have occasionally looked at them in EVs I’ve had and they go up and down.
Before I took delivery of my SF90 in early 2021, the factory told me to not keep the car on charge. Take it back to 100% after a drive, normally about 90 mins charging, and disconnect charger. Did that one time and left the car for 3 months while I travelled abroad. Asked my brother to run car every month for 10 mins, and recharge to 100% again, under 10 mins charging. At no point did it go below 80%, and when car was sold 18 months later with only 900 total miles covered, the SOH was 95%. Have no idea about 296 rules, but I don t think you should leave it on charge like the ICE cars, and I have also heard against the Ferrari grain, low mileage on the hybrids is not the way to go. Just reading this thread, makes me think why go hybrid at all, plenty of great Ferraris out there without a confusing thread like this. Shame.
Edited by maura on Monday 29th December 09:22
DMZ said:
Does a SoH value between 70-100% actually matter in a 296? Does a value of 73% mean it s slower than a car with a value of 93%? If not, what s the issue?
I hope you guys are aware that these software derived SoH numbers are pretty random? I have occasionally looked at them in EVs I ve had and they go up and down.
We need to separate the HV battery from the electric motor. A 65% SoH battery vs a 95% SoH battery will allow the electric motor to make the same peak horsepower. However, the 95% SoH battery will allow the electric motor to maintain that maximum horsepower for a longer period of time.I hope you guys are aware that these software derived SoH numbers are pretty random? I have occasionally looked at them in EVs I ve had and they go up and down.
So, the car with the higher SoH battery will be able to maintain maximum power for longer periods.
SoH is not a measurement, it's a calculation. It is influenced by the car's temperature, if the car has just been driven hard or sitting for long, cell balancing state, ambient temperature, and other variables. SoH is also best taken when the SoC is 20-80%. In an ideal world, you'd ensure all variables are constant. Obviously, that is impossible to do.
So asked the dealer today what the SOH measurement was on the car I m purchasing, as explained above this is on a 2 and a bit year old SF90 spider with sub 300 miles.
Aster receiving a picture of the reading, the SOH Measurement was 81% with the SOC max and min reading 93 and 94 respectively.
ETA the SOC average reading was 99 but not sure what relevance this has.
Aster receiving a picture of the reading, the SOH Measurement was 81% with the SOC max and min reading 93 and 94 respectively.
ETA the SOC average reading was 99 but not sure what relevance this has.
Trollbuster said:
So asked the dealer today what the SOH measurement was on the car I m purchasing, as explained above this is on a 2 and a bit year old SF90 spider with sub 300 miles.
Aster receiving a picture of the reading, the SOH Measurement was 81% with the SOC max and min reading 93 and 94 respectively.
ETA the SOC average reading was 99 but not sure what relevance this has.
Thank you very much for sharing that. Interesting how with just 300 miles it is at 81%. I'm waiting for a dealer to tell me the SoH on a 296 with <200 miles, three years old. I'll share the information as soon as I receive it. Aster receiving a picture of the reading, the SOH Measurement was 81% with the SOC max and min reading 93 and 94 respectively.
ETA the SOC average reading was 99 but not sure what relevance this has.
There's a school of thought that suggests when the SoH of a HV battery gets to about 70%, then Ferrari will likely replace it under warranty. Empirically that does not seem to hold true. I've visited and spoken to eight Ferrari dealerships. There are several 296s with SoHs in the low 70s and high 60s, and despite this Ferrari dealerships have them for sale as Ferrari Approved pre-owned cars. So, Ferrari is clearly demonstrating that just because a HVB has a SoH around 70%, they will NOT automatically replace the HVB. Only if it begins to regularly malfunction, then they will actually replace it.
Some had suggested to me in the past that the smart thing to do was buy a hybrid car with the lowest SoH on its HVB, so then Ferrari will have to quickly replace it and give me a brand new battery for free. Again, this does not seem to be what's actually happening at Ferrari dealerships.
Some had suggested to me in the past that the smart thing to do was buy a hybrid car with the lowest SoH on its HVB, so then Ferrari will have to quickly replace it and give me a brand new battery for free. Again, this does not seem to be what's actually happening at Ferrari dealerships.
Very interesting thread and discussion. Lots of very good points of information from people: thank you all.
[To put all of this discussion into context, if you an owner facing HV battery replacement as an out of pocket expense (ie. not covered by warranty) does anyone have current estimated costs from Authorised dealers for the new parts and labour costs? Are we talking £20k? More? Much more? Much, much, much, much more?] - EDIT. Just seen on another thread that estimated HV replacement is c. £30k (Was that inc VAT?)
Also this comment intrigues me:
[To put all of this discussion into context, if you an owner facing HV battery replacement as an out of pocket expense (ie. not covered by warranty) does anyone have current estimated costs from Authorised dealers for the new parts and labour costs? Are we talking £20k? More? Much more? Much, much, much, much more?] - EDIT. Just seen on another thread that estimated HV replacement is c. £30k (Was that inc VAT?)
Edited by XMA Simon on Thursday 8th January 15:22
Also this comment intrigues me:
ted 191 said:
...it's parked up at the main dealer waiting for it to be rejected and it s parked outside, because they are not allowed to leave them inside overnight?
Can others confirm this? Are dealers nervous about leaving hybrid cars inside their showrooms / workshops overnight or does this just apply to cars with known electrical faults? If a dealer is uncomfortable about leaving a hybrid under their roof overnight, how should I feel about leaving a hybrid in a double garage underneath my house! Under the bedroom no less!Edited by XMA Simon on Thursday 8th January 18:46
XMA Simon said:
Can others confirm this? Are dealers nervous about leaving hybrid cars inside their showrooms / workshops overnight or does this just apply to cars with known electrical faults? If a dealer is uncomfortable about leaving a hybrid under their roof overnight, how should I feel about leaving a hybrid in a double garage underneath my house! Under the bedroom no less!
Don't worry about leaving them overnight. One Ferrari dealer has loads of them sitting outside unplugged. I know, because I looked at all of them :-)Edited by XMA Simon on Thursday 8th January 18:46
LondonCarGuy said:
XMA Simon said:
Can others confirm this? Are dealers nervous about leaving hybrid cars inside their showrooms / workshops overnight or does this just apply to cars with known electrical faults? If a dealer is uncomfortable about leaving a hybrid under their roof overnight, how should I feel about leaving a hybrid in a double garage underneath my house! Under the bedroom no less!
Don't worry about leaving them overnight. One Ferrari dealer has loads of them sitting outside unplugged. I know, because I looked at all of them :-)Edited by XMA Simon on Thursday 8th January 18:46
My previous SF90 was sat on charge in my garage whilst not in use for the best part of 4 years. As was the 296Gts I briefly owned earlier last year.
The incoming SF90 Spider will also be sat there on charge whilst not in use, although as others have advised I may well intermittently charge it whilst not in use.
Trollbuster said:
I m going to guess it s cars with known electrical faults.
My previous SF90 was sat on charge in my garage whilst not in use for the best part of 4 years. As was the 296Gts I briefly owned earlier last year.
The incoming SF90 Spider will also be sat there on charge whilst not in use, although as others have advised I may well intermittently charge it whilst not in use.
The cars that I am referring to were at a Ferrari dealer all available for sale. None of these were in the Service Centre. This particular Ferrari dealer had five 296 GTBs, more than most I visited. One was in the show room plugged in. The others outside, unplugged. Also, there were several 296 GTS's outside in the same state. All for sale as Ferrari Approved.My previous SF90 was sat on charge in my garage whilst not in use for the best part of 4 years. As was the 296Gts I briefly owned earlier last year.
The incoming SF90 Spider will also be sat there on charge whilst not in use, although as others have advised I may well intermittently charge it whilst not in use.
They have some very nice well spec'ed cars...carbon fiber racing seats, forged wheels, lots of carbon all over them...most with 2-3k miles. And some of them are in the 70s SoH. In fact, one was at 73%. Imagine paying over £200k for your Ferrari Approved 296 GTB with only 2k miles on it, all the nice spec pieces on it...and your HV battery is already -27% degraded. That car is sitting there availalbe for sale as Ferrari Approved.
All you have to do is ask the question, and they will get you the SoH for the HVB. Be careful what you purchase, there are a lot of cars that look great on the surface, but their batteries are in poor condition.
It’s really concerning to see these batteries with such poor SOH after only a few thousand miles, especially as you wouldn’t see that on a Tesla with 100k miles (typically 80-85%).
One can only assume that part of the problem is the internal battery management by the car, and the other issue is how it is potentially stored.
Interestingly this is AI’s take on the situation..
It is becoming a significant talking point among owners and prospective buyers that Ferrari 296 GTB/GTS models often show a State of Health (SoH) in the 70% or 80% range with only 1,000–3,000 miles on the odometer.
The primary reasons for this "premature" degradation are a combination of how the car is used (or not used), the extreme operating environment, and the way the software calculates health.
1. Storage at 100% Charge
The most common cause of rapid SoH decline in these cars is leaving them on the battery conditioner (tender) indefinitely.
• Unlike a standard 12V trickle charger, keeping a High-Voltage (HV) lithium battery at 100% SoC (State of Charge) for weeks or months causes chemical stress.
• Most EV manufacturers recommend capping daily use at 80%, but the Ferrari system defaults to 100% when plugged in.
• Owners who "baby" the car by keeping it permanently plugged in while it sits in a garage are often inadvertently accelerating battery aging.
2. Thermal Stress and High-Performance Cycling
The 296 is a "highly strung" performance hybrid. The battery pack is located very close to the 120° V6 engine, which generates immense heat.
• Rapid Cycling: Unlike a Tesla or Prius that manages power for efficiency, the 296 battery is designed to discharge and recharge at massive rates (up to 167 cv from the electric motor).
• Heat Soak: High performance combined with engine heat can degrade the cells faster than in a daily-driver EV, especially if the car is driven hard and then parked without a proper cool-down.
3. SoH is a "Calculation," Not a "Measurement"
It is important to understand that the car does not have a sensor that "sees" battery health. Instead, the Battery Management System (BMS) estimates SoH based on:
• Voltage behavior during charging/discharging.
• Cell balancing across the pack.
• Internal resistance changes.
• Calibration Issues: If a car has only ever been driven short distances or has sat on a charger for months, the BMS hasn't seen a full "swing" of the battery (e.g., from 10% to 100%). This lack of data can lead to a conservative or "false" low SoH reading. Some owners report that "exercising" the battery through several deep cycles can actually see the SoH estimate rise slightly.
4. The "Garage Queen" Problem
Batteries, like the engines themselves, generally prefer regular use. Cars that sit for extended periods see their individual cells drift out of balance. When the dealer runs a health check, the most "unhealthy" or out-of-balance cell often dictates the SoH for the entire pack, resulting in a low percentage even if the car is nearly new.
Does it actually affect performance?
In most cases, a 296 with 75% SoH will still deliver the same peak horsepower as one with 100% SoH. However:
• Sustained Power: The lower SoH car will likely lose its "e-boost" sooner during a long track session.
• EV Range: The electric-only range will be noticeably shorter (e.g., dropping from the advertised 15 miles to 10–12 miles).
Ferrari's Warranty Stance
Ferrari recently introduced extended warranty programs (like Warranty Extension Hybrid) specifically to address these concerns. They now offer battery replacement at the 8th and 16th years of the car’s life, provided the car remains under their maintenance program. However, dealers often won't replace a battery under the standard 5-year hybrid warranty just for a "low SoH" number unless there is a specific cell failure or an error code that "bricks" the car.
One can only assume that part of the problem is the internal battery management by the car, and the other issue is how it is potentially stored.
Interestingly this is AI’s take on the situation..
It is becoming a significant talking point among owners and prospective buyers that Ferrari 296 GTB/GTS models often show a State of Health (SoH) in the 70% or 80% range with only 1,000–3,000 miles on the odometer.
The primary reasons for this "premature" degradation are a combination of how the car is used (or not used), the extreme operating environment, and the way the software calculates health.
1. Storage at 100% Charge
The most common cause of rapid SoH decline in these cars is leaving them on the battery conditioner (tender) indefinitely.
• Unlike a standard 12V trickle charger, keeping a High-Voltage (HV) lithium battery at 100% SoC (State of Charge) for weeks or months causes chemical stress.
• Most EV manufacturers recommend capping daily use at 80%, but the Ferrari system defaults to 100% when plugged in.
• Owners who "baby" the car by keeping it permanently plugged in while it sits in a garage are often inadvertently accelerating battery aging.
2. Thermal Stress and High-Performance Cycling
The 296 is a "highly strung" performance hybrid. The battery pack is located very close to the 120° V6 engine, which generates immense heat.
• Rapid Cycling: Unlike a Tesla or Prius that manages power for efficiency, the 296 battery is designed to discharge and recharge at massive rates (up to 167 cv from the electric motor).
• Heat Soak: High performance combined with engine heat can degrade the cells faster than in a daily-driver EV, especially if the car is driven hard and then parked without a proper cool-down.
3. SoH is a "Calculation," Not a "Measurement"
It is important to understand that the car does not have a sensor that "sees" battery health. Instead, the Battery Management System (BMS) estimates SoH based on:
• Voltage behavior during charging/discharging.
• Cell balancing across the pack.
• Internal resistance changes.
• Calibration Issues: If a car has only ever been driven short distances or has sat on a charger for months, the BMS hasn't seen a full "swing" of the battery (e.g., from 10% to 100%). This lack of data can lead to a conservative or "false" low SoH reading. Some owners report that "exercising" the battery through several deep cycles can actually see the SoH estimate rise slightly.
4. The "Garage Queen" Problem
Batteries, like the engines themselves, generally prefer regular use. Cars that sit for extended periods see their individual cells drift out of balance. When the dealer runs a health check, the most "unhealthy" or out-of-balance cell often dictates the SoH for the entire pack, resulting in a low percentage even if the car is nearly new.
Does it actually affect performance?
In most cases, a 296 with 75% SoH will still deliver the same peak horsepower as one with 100% SoH. However:
• Sustained Power: The lower SoH car will likely lose its "e-boost" sooner during a long track session.
• EV Range: The electric-only range will be noticeably shorter (e.g., dropping from the advertised 15 miles to 10–12 miles).
Ferrari's Warranty Stance
Ferrari recently introduced extended warranty programs (like Warranty Extension Hybrid) specifically to address these concerns. They now offer battery replacement at the 8th and 16th years of the car’s life, provided the car remains under their maintenance program. However, dealers often won't replace a battery under the standard 5-year hybrid warranty just for a "low SoH" number unless there is a specific cell failure or an error code that "bricks" the car.
s2000db said:
It s really concerning to see these batteries with such poor SOH after only a few thousand miles, especially as you wouldn t see that on a Tesla with 100k miles (typically 80-85%).
One can only assume that part of the problem is the internal battery management by the car, and the other issue is how it is potentially stored.
Interestingly this is AI s take on the situation..
It is becoming a significant talking point among owners and prospective buyers that Ferrari 296 GTB/GTS models often show a State of Health (SoH) in the 70% or 80% range with only 1,000 3,000 miles on the odometer.
The primary reasons for this "premature" degradation are a combination of how the car is used (or not used), the extreme operating environment, and the way the software calculates health.
1. Storage at 100% Charge
The most common cause of rapid SoH decline in these cars is leaving them on the battery conditioner (tender) indefinitely.
Unlike a standard 12V trickle charger, keeping a High-Voltage (HV) lithium battery at 100% SoC (State of Charge) for weeks or months causes chemical stress.
Most EV manufacturers recommend capping daily use at 80%, but the Ferrari system defaults to 100% when plugged in.
Owners who "baby" the car by keeping it permanently plugged in while it sits in a garage are often inadvertently accelerating battery aging.
2. Thermal Stress and High-Performance Cycling
The 296 is a "highly strung" performance hybrid. The battery pack is located very close to the 120° V6 engine, which generates immense heat.
Rapid Cycling: Unlike a Tesla or Prius that manages power for efficiency, the 296 battery is designed to discharge and recharge at massive rates (up to 167 cv from the electric motor).
Heat Soak: High performance combined with engine heat can degrade the cells faster than in a daily-driver EV, especially if the car is driven hard and then parked without a proper cool-down.
3. SoH is a "Calculation," Not a "Measurement"
It is important to understand that the car does not have a sensor that "sees" battery health. Instead, the Battery Management System (BMS) estimates SoH based on:
Voltage behavior during charging/discharging.
Cell balancing across the pack.
Internal resistance changes.
Calibration Issues: If a car has only ever been driven short distances or has sat on a charger for months, the BMS hasn't seen a full "swing" of the battery (e.g., from 10% to 100%). This lack of data can lead to a conservative or "false" low SoH reading. Some owners report that "exercising" the battery through several deep cycles can actually see the SoH estimate rise slightly.
4. The "Garage Queen" Problem
Batteries, like the engines themselves, generally prefer regular use. Cars that sit for extended periods see their individual cells drift out of balance. When the dealer runs a health check, the most "unhealthy" or out-of-balance cell often dictates the SoH for the entire pack, resulting in a low percentage even if the car is nearly new.
Does it actually affect performance?
In most cases, a 296 with 75% SoH will still deliver the same peak horsepower as one with 100% SoH. However:
Sustained Power: The lower SoH car will likely lose its "e-boost" sooner during a long track session.
EV Range: The electric-only range will be noticeably shorter (e.g., dropping from the advertised 15 miles to 10 12 miles).
Ferrari's Warranty Stance
Ferrari recently introduced extended warranty programs (like Warranty Extension Hybrid) specifically to address these concerns. They now offer battery replacement at the 8th and 16th years of the car s life, provided the car remains under their maintenance program. However, dealers often won't replace a battery under the standard 5-year hybrid warranty just for a "low SoH" number unless there is a specific cell failure or an error code that "bricks" the car.
The Tesla or Taycan do not have better batteries. What they do is their batteries are used very differently. As your AI post correctly explains, these small hybrid batteries in Ferrari/Lambo/McLaren/AMG/Porsche are put under much harsher conditions. As a result, they are degrading very quickly.One can only assume that part of the problem is the internal battery management by the car, and the other issue is how it is potentially stored.
Interestingly this is AI s take on the situation..
It is becoming a significant talking point among owners and prospective buyers that Ferrari 296 GTB/GTS models often show a State of Health (SoH) in the 70% or 80% range with only 1,000 3,000 miles on the odometer.
The primary reasons for this "premature" degradation are a combination of how the car is used (or not used), the extreme operating environment, and the way the software calculates health.
1. Storage at 100% Charge
The most common cause of rapid SoH decline in these cars is leaving them on the battery conditioner (tender) indefinitely.
Unlike a standard 12V trickle charger, keeping a High-Voltage (HV) lithium battery at 100% SoC (State of Charge) for weeks or months causes chemical stress.
Most EV manufacturers recommend capping daily use at 80%, but the Ferrari system defaults to 100% when plugged in.
Owners who "baby" the car by keeping it permanently plugged in while it sits in a garage are often inadvertently accelerating battery aging.
2. Thermal Stress and High-Performance Cycling
The 296 is a "highly strung" performance hybrid. The battery pack is located very close to the 120° V6 engine, which generates immense heat.
Rapid Cycling: Unlike a Tesla or Prius that manages power for efficiency, the 296 battery is designed to discharge and recharge at massive rates (up to 167 cv from the electric motor).
Heat Soak: High performance combined with engine heat can degrade the cells faster than in a daily-driver EV, especially if the car is driven hard and then parked without a proper cool-down.
3. SoH is a "Calculation," Not a "Measurement"
It is important to understand that the car does not have a sensor that "sees" battery health. Instead, the Battery Management System (BMS) estimates SoH based on:
Voltage behavior during charging/discharging.
Cell balancing across the pack.
Internal resistance changes.
Calibration Issues: If a car has only ever been driven short distances or has sat on a charger for months, the BMS hasn't seen a full "swing" of the battery (e.g., from 10% to 100%). This lack of data can lead to a conservative or "false" low SoH reading. Some owners report that "exercising" the battery through several deep cycles can actually see the SoH estimate rise slightly.
4. The "Garage Queen" Problem
Batteries, like the engines themselves, generally prefer regular use. Cars that sit for extended periods see their individual cells drift out of balance. When the dealer runs a health check, the most "unhealthy" or out-of-balance cell often dictates the SoH for the entire pack, resulting in a low percentage even if the car is nearly new.
Does it actually affect performance?
In most cases, a 296 with 75% SoH will still deliver the same peak horsepower as one with 100% SoH. However:
Sustained Power: The lower SoH car will likely lose its "e-boost" sooner during a long track session.
EV Range: The electric-only range will be noticeably shorter (e.g., dropping from the advertised 15 miles to 10 12 miles).
Ferrari's Warranty Stance
Ferrari recently introduced extended warranty programs (like Warranty Extension Hybrid) specifically to address these concerns. They now offer battery replacement at the 8th and 16th years of the car s life, provided the car remains under their maintenance program. However, dealers often won't replace a battery under the standard 5-year hybrid warranty just for a "low SoH" number unless there is a specific cell failure or an error code that "bricks" the car.
s2000db said:
It s really concerning to see these batteries with such poor SOH after only a few thousand miles, especially as you wouldn t see that on a Tesla with 100k miles (typically 80-85%).
One can only assume that part of the problem is the internal battery management by the car, and the other issue is how it is potentially stored.
Interestingly this is AI s take on the situation..
It is becoming a significant talking point among owners and prospective buyers that Ferrari 296 GTB/GTS models often show a State of Health (SoH) in the 70% or 80% range with only 1,000 3,000 miles on the odometer.
The primary reasons for this "premature" degradation are a combination of how the car is used (or not used), the extreme operating environment, and the way the software calculates health.
1. Storage at 100% Charge
The most common cause of rapid SoH decline in these cars is leaving them on the battery conditioner (tender) indefinitely.
Unlike a standard 12V trickle charger, keeping a High-Voltage (HV) lithium battery at 100% SoC (State of Charge) for weeks or months causes chemical stress.
Most EV manufacturers recommend capping daily use at 80%, but the Ferrari system defaults to 100% when plugged in.
Owners who "baby" the car by keeping it permanently plugged in while it sits in a garage are often inadvertently accelerating battery aging.
2. Thermal Stress and High-Performance Cycling
The 296 is a "highly strung" performance hybrid. The battery pack is located very close to the 120° V6 engine, which generates immense heat.
Rapid Cycling: Unlike a Tesla or Prius that manages power for efficiency, the 296 battery is designed to discharge and recharge at massive rates (up to 167 cv from the electric motor).
Heat Soak: High performance combined with engine heat can degrade the cells faster than in a daily-driver EV, especially if the car is driven hard and then parked without a proper cool-down.
3. SoH is a "Calculation," Not a "Measurement"
It is important to understand that the car does not have a sensor that "sees" battery health. Instead, the Battery Management System (BMS) estimates SoH based on:
Voltage behavior during charging/discharging.
Cell balancing across the pack.
Internal resistance changes.
Calibration Issues: If a car has only ever been driven short distances or has sat on a charger for months, the BMS hasn't seen a full "swing" of the battery (e.g., from 10% to 100%). This lack of data can lead to a conservative or "false" low SoH reading. Some owners report that "exercising" the battery through several deep cycles can actually see the SoH estimate rise slightly.
4. The "Garage Queen" Problem
Batteries, like the engines themselves, generally prefer regular use. Cars that sit for extended periods see their individual cells drift out of balance. When the dealer runs a health check, the most "unhealthy" or out-of-balance cell often dictates the SoH for the entire pack, resulting in a low percentage even if the car is nearly new.
Does it actually affect performance?
In most cases, a 296 with 75% SoH will still deliver the same peak horsepower as one with 100% SoH. However:
Sustained Power: The lower SoH car will likely lose its "e-boost" sooner during a long track session.
EV Range: The electric-only range will be noticeably shorter (e.g., dropping from the advertised 15 miles to 10 12 miles).
Ferrari's Warranty Stance
Ferrari recently introduced extended warranty programs (like Warranty Extension Hybrid) specifically to address these concerns. They now offer battery replacement at the 8th and 16th years of the car s life, provided the car remains under their maintenance program. However, dealers often won't replace a battery under the standard 5-year hybrid warranty just for a "low SoH" number unless there is a specific cell failure or an error code that "bricks" the car.
Exactly to my previous post, and what Factory techs told me, you don t want these on charge all the time like an ICE Ferrari. Run the car, get it back to 100%, take charger off. Over longer periods of storage, look at it 1 month later when it s probably dropped to 80%, repeat to 100% after a gentle start up to charge the 12v battery. I have never taken advice from a dealer tech has told me over a factory tech on these hybrid Ferraris. One can only assume that part of the problem is the internal battery management by the car, and the other issue is how it is potentially stored.
Interestingly this is AI s take on the situation..
It is becoming a significant talking point among owners and prospective buyers that Ferrari 296 GTB/GTS models often show a State of Health (SoH) in the 70% or 80% range with only 1,000 3,000 miles on the odometer.
The primary reasons for this "premature" degradation are a combination of how the car is used (or not used), the extreme operating environment, and the way the software calculates health.
1. Storage at 100% Charge
The most common cause of rapid SoH decline in these cars is leaving them on the battery conditioner (tender) indefinitely.
Unlike a standard 12V trickle charger, keeping a High-Voltage (HV) lithium battery at 100% SoC (State of Charge) for weeks or months causes chemical stress.
Most EV manufacturers recommend capping daily use at 80%, but the Ferrari system defaults to 100% when plugged in.
Owners who "baby" the car by keeping it permanently plugged in while it sits in a garage are often inadvertently accelerating battery aging.
2. Thermal Stress and High-Performance Cycling
The 296 is a "highly strung" performance hybrid. The battery pack is located very close to the 120° V6 engine, which generates immense heat.
Rapid Cycling: Unlike a Tesla or Prius that manages power for efficiency, the 296 battery is designed to discharge and recharge at massive rates (up to 167 cv from the electric motor).
Heat Soak: High performance combined with engine heat can degrade the cells faster than in a daily-driver EV, especially if the car is driven hard and then parked without a proper cool-down.
3. SoH is a "Calculation," Not a "Measurement"
It is important to understand that the car does not have a sensor that "sees" battery health. Instead, the Battery Management System (BMS) estimates SoH based on:
Voltage behavior during charging/discharging.
Cell balancing across the pack.
Internal resistance changes.
Calibration Issues: If a car has only ever been driven short distances or has sat on a charger for months, the BMS hasn't seen a full "swing" of the battery (e.g., from 10% to 100%). This lack of data can lead to a conservative or "false" low SoH reading. Some owners report that "exercising" the battery through several deep cycles can actually see the SoH estimate rise slightly.
4. The "Garage Queen" Problem
Batteries, like the engines themselves, generally prefer regular use. Cars that sit for extended periods see their individual cells drift out of balance. When the dealer runs a health check, the most "unhealthy" or out-of-balance cell often dictates the SoH for the entire pack, resulting in a low percentage even if the car is nearly new.
Does it actually affect performance?
In most cases, a 296 with 75% SoH will still deliver the same peak horsepower as one with 100% SoH. However:
Sustained Power: The lower SoH car will likely lose its "e-boost" sooner during a long track session.
EV Range: The electric-only range will be noticeably shorter (e.g., dropping from the advertised 15 miles to 10 12 miles).
Ferrari's Warranty Stance
Ferrari recently introduced extended warranty programs (like Warranty Extension Hybrid) specifically to address these concerns. They now offer battery replacement at the 8th and 16th years of the car s life, provided the car remains under their maintenance program. However, dealers often won't replace a battery under the standard 5-year hybrid warranty just for a "low SoH" number unless there is a specific cell failure or an error code that "bricks" the car.
LondonCarGuy said:
The cars that I am referring to were at a Ferrari dealer all available for sale. None of these were in the Service Centre. This particular Ferrari dealer had five 296 GTBs, more than most I visited. One was in the show room plugged in. The others outside, unplugged. Also, there were several 296 GTS's outside in the same state. All for sale as Ferrari Approved.
They have some very nice well spec'ed cars...carbon fiber racing seats, forged wheels, lots of carbon all over them...most with 2-3k miles. And some of them are in the 70s SoH. In fact, one was at 73%. Imagine paying over £200k for your Ferrari Approved 296 GTB with only 2k miles on it, all the nice spec pieces on it...and your HV battery is already -27% degraded. That car is sitting there availalbe for sale as Ferrari Approved.
All you have to do is ask the question, and they will get you the SoH for the HVB. Be careful what you purchase, there are a lot of cars that look great on the surface, but their batteries are in poor condition.
I’m highly skeptical that it’s as important as you think it is. It’s not an EV so it’s not like you’re losing 23% range. Battery size in a PHEV is nearly entirely a CO2 fudge. I’d say you wouldn’t even notice it. With your logic, a supercar fitted with a battery half the size is half as good. Like the Lambo Revuelto for example. Going by reviews, it seems to be working quite well despite its smaller battery capacity. They have some very nice well spec'ed cars...carbon fiber racing seats, forged wheels, lots of carbon all over them...most with 2-3k miles. And some of them are in the 70s SoH. In fact, one was at 73%. Imagine paying over £200k for your Ferrari Approved 296 GTB with only 2k miles on it, all the nice spec pieces on it...and your HV battery is already -27% degraded. That car is sitting there availalbe for sale as Ferrari Approved.
All you have to do is ask the question, and they will get you the SoH for the HVB. Be careful what you purchase, there are a lot of cars that look great on the surface, but their batteries are in poor condition.
But of course once people start to stress about it on the internet then it becomes a thing and it’s obviously not all that impressive that it’s degrading so much.
DMZ said:
I m highly skeptical that it s as important as you think it is. It s not an EV so it s not like you re losing 23% range. Battery size in a PHEV is nearly entirely a CO2 fudge. I d say you wouldn t even notice it. With your logic, a supercar fitted with a battery half the size is half as good. Like the Lambo Revuelto for example. Going by reviews, it seems to be working quite well despite its smaller battery capacity.
But of course once people start to stress about it on the internet then it becomes a thing and it s obviously not all that impressive that it s degrading so much.
The battery is different than the electric motor. A 60% SoH battery and a 95% SoH battery will both allow the electric motor to make the same peak horsepower. However, the 95% SoH battery will allow the electric motor to maintain that peak horsepower for a longer period of time.But of course once people start to stress about it on the internet then it becomes a thing and it s obviously not all that impressive that it s degrading so much.
DMZ said:
I m highly skeptical that it s as important as you think it is. It s not an EV so it s not like you re losing 23% range. Battery size in a PHEV is nearly entirely a CO2 fudge. I d say you wouldn t even notice it. With your logic, a supercar fitted with a battery half the size is half as good. Like the Lambo Revuelto for example. Going by reviews, it seems to be working quite well despite its smaller battery capacity.
But of course once people start to stress about it on the internet then it becomes a thing and it s obviously not all that impressive that it s degrading so much.
I think this is a fair comment. A 75% SoC battery is not bricked condition and the car does not become unusable as a result. The 296 is primarily a bonkers, over the top road car. And the fact that Ferrari are not replacing these batteries automatically at 70-80% ish SoC suggests that it does not materially impact the normal function of the car. Where you might notice an aged battery as opposed to a fresh one is if you were driving very quickly, Nürburgring ring laps in qualifying mode which are 7-8 mins per lap if you are very skilled. You might get to the point where you run out of torque fill and have to recharge the HV battery before another hot lap. I don't think that will be a problem to most owners much of the time for fast road driving.But of course once people start to stress about it on the internet then it becomes a thing and it s obviously not all that impressive that it s degrading so much.
I suppose where it would be a problem is where short boost endurance becomes a noticeable problem for fast road drivers that enjoy frequent track days or in the case where HV battery degradation causes repeated electrical gremlins. The former criterion clearly has some degree of subjectivity and it would be helpful for buyers to understand the criterion on which Ferrari would agree to HV battery warranty claims. The latter - electrical gremlins - are much clearer cut but I would imagine owners would have to endure more than one bricked car incident before dealers agree to an HV battery replacement on warranty.
Another thing for buyers to consider is this: if I am buying a pre owned 296 with say 70% SoC the battery will still most likely be fine for general road use. Particularly if I understand how to condition and use the battery without further accelerating its aging. However it will inevitably age. And after say three years I want to sell the car the battery is at what... 60% SoC? If you are lucky? So what will the prospective buyer be thinking... that they have a £30k bill ahead of them. So I think these cars will continue to depreciate quite a lot and we've not seen the nadir on them yet despite them already having depreciated so heavily.
The advice from London Car Guy to check SoC on any car you are looking at is no doubt good advice as an important data point to take into account alongside colours, options and so on. I think SoC far more relevant data point on these cars than milage.
Great debate everyone. I welcome everyone's views.
I keep asking myself this, when I look at pre-owned Ferrari Approved 296 GTBs, many of them have similar miles, similar specs, median price is £205k, but some are under 75% SoH and some are over 90% SoH. Age and miles do not appear correlated with SoH generally. So, all else being similar, I guess I'll go for a car with an SoH >90%, it certainly doesn't cost any more money.
From my technical dive into this:
What actually happens when the HV battery SoH gets low?
If you take a Ferrari hybrid with, say, 65% SoH, what are the realistic failure modes?
1. Lower SoH = higher internal resistance = more stress every time the pack is used
As the battery ages, resistance goes up. That leads to:
• more voltage sag when you ask for power
• more heat for the same current
• more thermal load on the cells
Which pushes the pack closer to:
• thermal derate
• cell imbalance
• BMS protection limits
A pack at 65% SoH is running with much less headroom.
2. Ferrari’s BMS masks degradation… until it can’t
The system is pretty conservative and hides a lot of ageing behind software.
But once it sees:
• repeated imbalance
• big voltage drops under load
• thermal spikes
• trouble maintaining the buffer
…it starts throwing the usual hybrid warnings:
• Hybrid system fault
• Reduced performance
• E‑drive unavailable
• Battery protection mode
A 65% pack is simply closer to tripping these thresholds.
3. Low SoH = higher chance of cell imbalance (the main reason packs get replaced)
Ferrari HV batteries rarely get swapped because “capacity is low”.
They get swapped because:
• one or more cells drift out of balance
• the BMS can’t pull them back
• voltage spread becomes too large
Lower SoH makes imbalance more likely, so you see:
• uneven cell voltages
• uneven temperatures
• constant BMS balancing attempts
That’s what ultimately forces a replacement.
4. Thermal behaviour gets noticeably worse below ~70%
As resistance rises, the pack:
• heats up faster
• cools down slower
• hits thermal limits sooner
Ferrari’s hybrid system is very temperature‑sensitive, so a 65% pack will:
• derate more often
• lose e‑boost earlier
• rely on the engine to recharge more aggressively
Which accelerates wear even further.
Bottom line:
As SoH drops, the pack loses voltage, thermal, and balancing margin. The lower it gets, the more likely you are to see hybrid warnings, reduced performance, and ultimately the conditions that lead to replacement.
I keep asking myself this, when I look at pre-owned Ferrari Approved 296 GTBs, many of them have similar miles, similar specs, median price is £205k, but some are under 75% SoH and some are over 90% SoH. Age and miles do not appear correlated with SoH generally. So, all else being similar, I guess I'll go for a car with an SoH >90%, it certainly doesn't cost any more money.
From my technical dive into this:
What actually happens when the HV battery SoH gets low?
If you take a Ferrari hybrid with, say, 65% SoH, what are the realistic failure modes?
1. Lower SoH = higher internal resistance = more stress every time the pack is used
As the battery ages, resistance goes up. That leads to:
• more voltage sag when you ask for power
• more heat for the same current
• more thermal load on the cells
Which pushes the pack closer to:
• thermal derate
• cell imbalance
• BMS protection limits
A pack at 65% SoH is running with much less headroom.
2. Ferrari’s BMS masks degradation… until it can’t
The system is pretty conservative and hides a lot of ageing behind software.
But once it sees:
• repeated imbalance
• big voltage drops under load
• thermal spikes
• trouble maintaining the buffer
…it starts throwing the usual hybrid warnings:
• Hybrid system fault
• Reduced performance
• E‑drive unavailable
• Battery protection mode
A 65% pack is simply closer to tripping these thresholds.
3. Low SoH = higher chance of cell imbalance (the main reason packs get replaced)
Ferrari HV batteries rarely get swapped because “capacity is low”.
They get swapped because:
• one or more cells drift out of balance
• the BMS can’t pull them back
• voltage spread becomes too large
Lower SoH makes imbalance more likely, so you see:
• uneven cell voltages
• uneven temperatures
• constant BMS balancing attempts
That’s what ultimately forces a replacement.
4. Thermal behaviour gets noticeably worse below ~70%
As resistance rises, the pack:
• heats up faster
• cools down slower
• hits thermal limits sooner
Ferrari’s hybrid system is very temperature‑sensitive, so a 65% pack will:
• derate more often
• lose e‑boost earlier
• rely on the engine to recharge more aggressively
Which accelerates wear even further.
Bottom line:
As SoH drops, the pack loses voltage, thermal, and balancing margin. The lower it gets, the more likely you are to see hybrid warnings, reduced performance, and ultimately the conditions that lead to replacement.
Also the failure rate for Li-Ion batteries (in general - not just for cars) is something like 1 in a million. While that sounds good that is one in a million cells and some of these auto batteries have hundreds to thousands of cells. And if they short circuit with significant charge stored they catch fire and it is BBQ time.
So besides the debate around performance all this battery management software is there to minimise the risk of a fire event. So when the software says to switch the battery it becomes a real safety priority to get it done.
Ferrari, Porsche and all the other car companies need to improve communication and transparency particularly in these performance hybrids where rapid, frequent charge / discharge cycles are placing heavy loads on HV batteries.
I suppose now we can see why the 296 Challenge car does without the HV / hybrid gubbins. Imagine a road version of that... it would sell like hotcakes!
It used to be quite simple to evaluate a car. Now you need degrees in chemistry, engineering and IT / software to evaluate them. LOLs.
So besides the debate around performance all this battery management software is there to minimise the risk of a fire event. So when the software says to switch the battery it becomes a real safety priority to get it done.
Ferrari, Porsche and all the other car companies need to improve communication and transparency particularly in these performance hybrids where rapid, frequent charge / discharge cycles are placing heavy loads on HV batteries.
I suppose now we can see why the 296 Challenge car does without the HV / hybrid gubbins. Imagine a road version of that... it would sell like hotcakes!
It used to be quite simple to evaluate a car. Now you need degrees in chemistry, engineering and IT / software to evaluate them. LOLs.
Edited by XMA Simon on Friday 9th January 19:15
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