Tesla P85D vs Dodge Hellcat
Discussion
K50 DEL said:
Is the biggest problems with EVs not their range and charging time... if I want to do a 600 mile road trip in a day (something I do fairly often) I don't want to have to stop halfway for 30 minutes / an hour / 12 hours to charge the car
You wont necessarily have to. Battery swaps are a possibility and can be done in half the time it takes to fill a tank.https://www.youtube.com/watch?v=H5V0vL3nnHY
Tesla are already trialing their first swap station with customers in LA. The only catch is swaps would carry a cost probably something similar to fueling a tank. Their slogan is, "Fast, or free"
So if you're in a hurry then swap. If not, stretch your legs, take a piss, have a bite to eat and 20min later you're on your way for free.
Looks like there is a deal for that 8th year battery pack worry: "A separate battery replacement guarantee takes effect after the eighth year at a cost of US$12,000 for the 85 kWh battery.
Charging many batteries weekly for work I currently know of no battery that isn't rather past it after 4 years - range at year 6 may well be under 200 miles?
I'd imagine you can offset the lack of need for expensive oil based servicing annually against battery 'erosion' though? Lots of interesting sums to be done!
Charging many batteries weekly for work I currently know of no battery that isn't rather past it after 4 years - range at year 6 may well be under 200 miles?
I'd imagine you can offset the lack of need for expensive oil based servicing annually against battery 'erosion' though? Lots of interesting sums to be done!
Battery chemistry & design can varies a lot, you can prioritize energy density, or cycle life etc. Your experience with some other cells is partly relevant but doesn't apply directly.
Charging strategies also make a considerable difference. Tesla don't top off the battery unless you specifically set it to max range mode and then it nags you if you leave it that way for days.
The idea is to stay away from the extreme high and low levels for routine daily use when you don't need all the range.
Dunno what they'd be like after 8 years of 'fair use', but I'm not assuming good or bad at this stage.
One thing for sure, unlike a petrol car engine you'll be able to do a test & diag on the battery and get a definitive answer as to how shagged it is. Trivially easy to swap in a new one, which will certainly have better capacity than the original even when it was new so the replacement will also be an upgrade.
It will be interesting to see how much they can drop the cost of the batteries in 8 years. Its still going to be several thousand but that's a lot more digestible than 12k.
Interesting Dave. Whole new way of thinking; lots to learn.
There is no transmission to service/wear/out fix but are the motors 'simple' with just a few shaft bearings to wear out, as opposed to the hundreds of things that can fail in an an internal combustion engine? Even read that they may have cracked how to double a Li Ion battery's capacity the other day - http://www.scientificamerican.com/article/secretiv...
Seems to be taking about a 100Kw from mains for a full charge? That is a shedload of power if we all start doing it mind - lights will dim!
There is no transmission to service/wear/out fix but are the motors 'simple' with just a few shaft bearings to wear out, as opposed to the hundreds of things that can fail in an an internal combustion engine? Even read that they may have cracked how to double a Li Ion battery's capacity the other day - http://www.scientificamerican.com/article/secretiv...
Seems to be taking about a 100Kw from mains for a full charge? That is a shedload of power if we all start doing it mind - lights will dim!
There is a single reduction gear & open diff. No gear changes required, reverse by running the motor backwards (that might mean you could do 120mph backwards if the programming allowed it...)
Limited slip action across the axle achieved by applying brake to the slipping wheel as commonly done by various existing stability & TC systems.
Motor is brushless 3 phase AC induction, so nothing in the way of rubbing / wearing bits just some bearings as you say. Cooling for high steady-state was obviously challenging for them so I wonder how they handle cooling the rotor and if that introduces any weaknesses.
In short, vastly fewer moving parts & (mechanical) complexity so if sized right & quality ok there is potential for great durability.
Regarding battery developments, they do come (last month Tesla announced a 30% range bump for the Roadster) but Musk has said "Battery breakthroughs are announced every few months but the BS factor is outrageous". Basically they always have some huge tradeoff that makes them irrelevant for real use, like cycle life.
That said, imagine if there were a tech breakthrough in batteries or ultra caps with some radically new chem and overnight a 600 mile range Tesla was possible. That would seriously disrupt the status quo & the industry would s
t itself. Super unlikely I'm sure, instead we'll see further creeping improvement but it would be funny.
The main improvement we'll see will be cost via process & scale. Tesla gigafactory targeting a 30% cost reduction in the pack by the time the Model3 needs it in a few years. They need that kind of thing to make the cheap small car viable.
The supercharger stations were originally 90kW and have now been dialed up to 130kW in a few stages as they have developed, tested, and got more familiar with what the batteries can tolerate. Charging times also improved by tweaking the tail-off charging curve (go harder for longer) for the same reason.
130kW is way way higher than other elec cars because they are bypassing the onboard charger and running DC directly into the batteries.
At home even with all the optional bits - high current 40A outlets plus dual chargers in the car it will still take 4hrs or so from empty to full and yeah, 100kWh is a big chunk of juice but,
Home charging is mostly overnight when supply is plentiful, which is why the off peak rates are cheaper in the first place.
Day charging at supercharger stations can limit the impact on the grid with large stationary batteries to buffer from both the solar at the station and grid if required. A decent chunk of the gigafactory production is apparently for this purpose.
Long term when serious numbers of elec appear on the roads power generation is going to need a serious rethink but lots of options
Limited slip action across the axle achieved by applying brake to the slipping wheel as commonly done by various existing stability & TC systems.
Motor is brushless 3 phase AC induction, so nothing in the way of rubbing / wearing bits just some bearings as you say. Cooling for high steady-state was obviously challenging for them so I wonder how they handle cooling the rotor and if that introduces any weaknesses.
In short, vastly fewer moving parts & (mechanical) complexity so if sized right & quality ok there is potential for great durability.
Regarding battery developments, they do come (last month Tesla announced a 30% range bump for the Roadster) but Musk has said "Battery breakthroughs are announced every few months but the BS factor is outrageous". Basically they always have some huge tradeoff that makes them irrelevant for real use, like cycle life.
That said, imagine if there were a tech breakthrough in batteries or ultra caps with some radically new chem and overnight a 600 mile range Tesla was possible. That would seriously disrupt the status quo & the industry would s
t itself. Super unlikely I'm sure, instead we'll see further creeping improvement but it would be funny.The main improvement we'll see will be cost via process & scale. Tesla gigafactory targeting a 30% cost reduction in the pack by the time the Model3 needs it in a few years. They need that kind of thing to make the cheap small car viable.
The supercharger stations were originally 90kW and have now been dialed up to 130kW in a few stages as they have developed, tested, and got more familiar with what the batteries can tolerate. Charging times also improved by tweaking the tail-off charging curve (go harder for longer) for the same reason.
130kW is way way higher than other elec cars because they are bypassing the onboard charger and running DC directly into the batteries.
At home even with all the optional bits - high current 40A outlets plus dual chargers in the car it will still take 4hrs or so from empty to full and yeah, 100kWh is a big chunk of juice but,
Home charging is mostly overnight when supply is plentiful, which is why the off peak rates are cheaper in the first place.
Day charging at supercharger stations can limit the impact on the grid with large stationary batteries to buffer from both the solar at the station and grid if required. A decent chunk of the gigafactory production is apparently for this purpose.
Long term when serious numbers of elec appear on the roads power generation is going to need a serious rethink but lots of options
Edited by SpeedyDave on Wednesday 21st January 18:28
Gassing Station | General Gassing | Top of Page | What's New | My Stuff