Battery Brain

Battery Brain

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Discussion

aide

Original Poster:

2,276 posts

164 months

Wednesday 15th February 2012
quotequote all
My Battery gave up last week so, along with a new battery, I fitted a battery brain.

It wasn't too hard to fit and along with the battery brain I also needed a +ive battery terminal and a piece of battery cable.



FarmyardPants

4,108 posts

218 months

Thursday 16th February 2012
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Very nice. What is a battery brain?

aide

Original Poster:

2,276 posts

164 months

Thursday 16th February 2012
quotequote all
http://www.batterybrain.co.uk/faq.html

It's a battery isolation switch that operates by remote control.

Except it has an extra feature that automatically cuts itself off if it senses that power levels in the battery drop too low.

Which saves you getting caught with not enough power left in the battery to start the car if laid up with the alarm on etc..

So you can use it to either cut power to the whole car via it's remote.

Or you can leave it on and it'll do it for you if your battery gets drained by the alarm or clock, or if you leave something like the satnav plugged in or a light on etc..

Tanguero

4,535 posts

201 months

Thursday 16th February 2012
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The alarm siren on a Cerb will go off if the battery is disconnected while the alarm is switched on! Still - I suppose it will tell you when your battery is low!

aide

Original Poster:

2,276 posts

164 months

Thursday 16th February 2012
quotequote all
Tanguero said:
The alarm siren on a Cerb will go off if the battery is disconnected while the alarm is switched on! Still - I suppose it will tell you when your battery is low!
I believe it's the other way around, If the battery is connected the alarm activates.
Once the battery is reconnected and the alarm automatically arms itself you just have to deactivate it before it goes off.

Jubes

79 posts

153 months

Thursday 16th February 2012
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Excellent job aide.

We've been discussing this very product in the thread below:

http://www.pistonheads.com/gassing/topic.asp?h=0&a...

How did you secure the Battery Brain to the vehicle and do you have any close up pictures of the install please?

Many thanks.

julian64

14,317 posts

254 months

Thursday 16th February 2012
quotequote all
Hmm, not sure about this, aren't the adaptives reset if you disconnect the ECU from the battery for a length of time. If so every time you start the car you'll have reset the adaptivs and the car will run like a dog for a few hours. Also you'll be effectively destroying the batteries in the NVram in the eCU plus the batteries in the alarm system?

aide

Original Poster:

2,276 posts

164 months

Thursday 16th February 2012
quotequote all
Jubes said:
Excellent job aide.

We've been discussing this very product in the thread below:

http://www.pistonheads.com/gassing/topic.asp?h=0&a...

How did you secure the Battery Brain to the vehicle and do you have any close up pictures of the install please?

Many thanks.
Thanks Jubes,

I did have a good read of the thread above before I started, which was really helpful.

With the two cables secured to each side of the battery brain, and when it's all fitted there is virtually no play at all.

But I am waiting on a piece of aluminium plate from www.aluminiumwarehouse.co.uk

Once it arrives I'll bend it at 90 degrees and mount the battery brain to one side of it and then slide the other side under the battery to secure it. Once the battery is bolted down it'll hold the plate with the battery brain attached.

However, I did stick a sheet of 2mm thick adhesive neoprene foam to the side of the battery and then put a rectangular piece of hard plastic between the battery brain and the battery just in case engine vibration will cause wear while I'm waiting on the aluminium.

The original +ive cables don't need to be cut at all. I'll post a few more pics over the weekend.

Tanguero

4,535 posts

201 months

Thursday 16th February 2012
quotequote all
aide said:
Tanguero said:
The alarm siren on a Cerb will go off if the battery is disconnected while the alarm is switched on! Still - I suppose it will tell you when your battery is low!
I believe it's the other way around, If the battery is connected the alarm activates.
Once the battery is reconnected and the alarm automatically arms itself you just have to deactivate it before it goes off.
No, according to the Meta alarm manual (and practical experience on my car) if alarm is armed and you disconnect the battery the alarm will sound using the self powered siren. The point is that it prevents a thief from disarming the alarm by disconnecting the battery. The battery in the siren unit can last for several hours at full blast!

If you disconnect the battery when the alarm is not armed and then reconnect it, the alarm will automatically arm as you say.


aide

Original Poster:

2,276 posts

164 months

Thursday 16th February 2012
quotequote all
Tanguero said:
No, according to the Meta alarm manual (and practical experience on my car) if alarm is armed and you disconnect the battery the alarm will sound using the self powered siren. The point is that it prevents a thief from disarming the alarm by disconnecting the battery. The battery in the siren unit can last for several hours at full blast!

If you disconnect the battery when the alarm is not armed and then reconnect it, the alarm will automatically arm as you say.
That's a bit of a bummer actually, unless you always disconect the battery and disarm the alarm.

julian64 said:
Hmm, not sure about this, aren't the adaptives reset if you disconnect the ECU from the battery for a length of time. If so every time you start the car you'll have reset the adaptivs and the car will run like a dog for a few hours. Also you'll be effectively destroying the batteries in the NVram in the eCU plus the batteries in the alarm system?
I guess the lithium battery in the NVram, even though it's replacable, would be better off connected to the battery all the time.


Plenty of food for thought, at least I didn't cut the original cables! thanks guys






FarmyardPants

4,108 posts

218 months

Friday 17th February 2012
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Perhaps you could wire a small 12v battery in parallel with the main battery to run the car's systems (clock, alarm, ecu etc). It would get charged when the car is running.
Also presumably the remote control receiver needs a bit of power - does it get that from the car battery? I don't suppose it takes much juice though.

Chimpandtonic

9,637 posts

179 months

Friday 17th February 2012
quotequote all
It,s worth noting here that the BatteryBrain provides two male spades on the permanently connected side of the unit.

The idea is you can use these two connections to run your clock and radio so the time & channel pre-sets are retained.

Obviously you are then re-introducing a parasitic drain from these two components, but the option is there if you need to use it.

Actually it's no different to running a live feed directly off the battery post, if you are plumbing in a trickle charger you would also connect it to the permanent live side of the BB.

gerradiuk

1,669 posts

195 months

Friday 17th February 2012
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I have a battery switch on mine & its never been a problem at all. It runs absolutely fine every time once warmed up properly.

julian64

14,317 posts

254 months

Friday 17th February 2012
quotequote all
gerradiuk said:
I have a battery switch on mine & its never been a problem at all. It runs absolutely fine every time once warmed up properly.
But you are making future problems for yourself. The battery in the NVRAM isn't working while the main car battery is connected and neither is the ni cad battery in the alarm.

The Meta alarm is too old to be lithium, and nicads don't do any length of time flat very well.

If you are going to connect a small battery for the alarm and the ECU you might as well connect the main one with a battery conditioner attached, as apart from the alarm and the ECU I don't think there should be any other drain.

aide

Original Poster:

2,276 posts

164 months

Friday 17th February 2012
quotequote all
julian64 said:
gerradiuk said:
I have a battery switch on mine & its never been a problem at all. It runs absolutely fine every time once warmed up properly.
But you are making future problems for yourself. The battery in the NVRAM isn't working while the main car battery is connected and neither is the ni cad battery in the alarm.

The Meta alarm is too old to be lithium, and nicads don't do any length of time flat very well.

If you are going to connect a small battery for the alarm and the ECU you might as well connect the main one with a battery conditioner attached, as apart from the alarm and the ECU I don't think there should be any other drain.
It's a little bit worse than that because the lithium battery in the NVram isn't rechargeable and is integrated into the NVram die itself. So if you leave the car completely isolated most of the time the NVram battery slowly drains.

When that happens, if you want the adaptive map's to be remembered in between battery disconnects, you have to replace the whole NVram chip because the battery is not a separate item.

I'm not sure if the chip is soldered on to the board either, so it could be a bit more of a pain to replace. Having said that, it's said that the life expetantacy of the NVram battery is 10 years and even though most cerbs are pushing 10 years of age, most of that time the main battery in the car would have been connected so the NVram battery wouldn't have been used to keep the NVram data safe.

I guess the battery brain is good if it's used as a battery fail-safe only and not as a battery isolation solution, but the problem there is, if the battery brain senses the need to isolate the battery and cuts power, then the alarm will go off!

I think I'll put the old battery back in the car with the the battery brain connected, leave the lights on, activate the alarm and wait until the battery brain isolator kicks in. When it does, if the alarm goes off then it's not worth having because the only way of getting around this would be to use one of the male spades on the permanently connected side of the bb, that Chimpandtonic mentioned, to stop the alarm going off, but doing that would defeat the purpose as the battery would still drain!

I think Julian64 is 100% right, the main battery shouldn't be disconnected and ideally put on a trickle charger.

TVdinneR

240 posts

150 months

Friday 17th February 2012
quotequote all
julian64 said:
Hmm, not sure about this, aren't the adaptives reset if you disconnect the ECU from the battery for a length of time. If so every time you start the car you'll have reset the adaptivs and the car will run like a dog for a few hours. Also you'll be effectively destroying the batteries in the NVram in the eCU plus the batteries in the alarm system?
What would you consider to be a "length of time" ?
Only asking as recently both the 4.2 & the 4.5 main batteries didnt cope too well with the cold spell. This coupled with the fact they weren`t being used.
Both batteries were removed, fully charged, conditioned and left out of the vehicles for a while, ie the 4.5 for 2 months and the 4.2 for 3 weeks.
The 4.5 is now being used daily just now and battery is fine, & car running great - touch wood.
The 4.2 is being used on nice days only at the moment and each time its put away for a week or two I disconnect the battery, with no apparent adverse effects when reconnected - also running great - also touch wood.
Am I to assume, from what I`m reading, this is not good practice !

Tanguero

4,535 posts

201 months

Friday 17th February 2012
quotequote all
Surely the only drains on the battery when the car is not in use are those from the alarm, radio and possibly ECU. Doesn't using a Battery Brain but bypassing it for those loads means that it wont actually be doing anything!

aide

Original Poster:

2,276 posts

164 months

Friday 17th February 2012
quotequote all
TVdinneR said:
What would you consider to be a "length of time" ?
Only asking as recently both the 4.2 & the 4.5 main batteries didnt cope too well with the cold spell. This coupled with the fact they weren`t being used.
Both batteries were removed, fully charged, conditioned and left out of the vehicles for a while, ie the 4.5 for 2 months and the 4.2 for 3 weeks.
The 4.5 is now being used daily just now and battery is fine, & car running great - touch wood.
The 4.2 is being used on nice days only at the moment and each time its put away for a week or two I disconnect the battery, with no apparent adverse effects when reconnected - also running great - also touch wood.
Am I to assume, from what I`m reading, this is not good practice !
It may or may not be the case unless the ecu draws current from the main battery, when the ignittion is off, to maintain the state in the VNram. If it does, then leaving the battery connected would preserve the NVram battery. If it doesn't then the NVram battery would always be in a state of decay when the ignition is off and ultimately would discharge to the point where it could no longer remember the adaptive data in between engine cycles. And a situation like that would manifest itself as just poor start up performance until the adaptives were re-learned.

Does anyone know if the ecu draws current from the main battery, when the ignittion is off, to maintain the state in the VNram?

Chimpandtonic

9,637 posts

179 months

Friday 17th February 2012
quotequote all
It's probably a different story on the more modern T cars, but on a Chimaera the BatteryBrain does not cause problems.

Park up, lock the doors with the car fob, and then use the BB remote to disconnect the battery.

No Meta alarm activation at all.

When returning to the car, use the BB remote to re-connect the battery, unlock the doors with the fob, get in & drive off.

Again, no activation of the alarm.

I'm not quite sure why the alarm doesn't activate, you would think it would.

After all it's meant to detect a car thief disconnecting the battery right?.

But in the real world the truth is there is no such alarm activation, well in a Chimaera with a Meta system anyway.

The most you need to do is press the car fob once more to make sure the immobiliser is disconnected & the system ready for you to start the car.

The car can be left for up to two months using the BB & it starts fine, so the BB is a great solution for those of us who store our cars where there is no mains power.

On the ECU question it's worth pointing out a Chimaera runs the stone age Lucas 14CUX system, which while crude is not troubled by such connections & reconnections of it's power supply as far as I can tell.

How a T car ECU will cope is an unknown to me.

Clearly a trickle charger is the best option, but if no mains power is available the BB is a great solution & more reliable than solar in my personal experience.

crypto

232 posts

241 months

Friday 17th February 2012
quotequote all
julian64 said:
But you are making future problems for yourself. The battery in the NVRAM isn't working while the main car battery is connected and neither is the ni cad battery in the alarm.

The Meta alarm is too old to be lithium, and nicads don't do any length of time flat very well.

If you are going to connect a small battery for the alarm and the ECU you might as well connect the main one with a battery conditioner attached, as apart from the alarm and the ECU I don't think there should be any other drain.
I'm surprised there is a NVRAM in the ECU, because this sounds like a ticking time bomb. After 10 years these batteries are usually dead, so are the nicads in the alarm. Whenever the main car battery is changed or disconnected one would have this problem ? How long does it take to calculate those values once the engine is started ? I guess a default data-set is loaded whenever a power-loss was detected ?