Flattened auxiliary battery - any consequences?

[AlexBorro]

There are commercial solutions available for this. Plug and play.

LiFePO4 replacement for acid lead batteries:

http://www.go-aliant.com/lithium/index. ... t-serie-ea

A friend of mine uses one of this to replace its motorcycle one. Very happy with the solution.

Cheers.

Alex.

[STS134]

I do have one of those testers... Also thought they are a great idea, mine even tells me what the internal resistance is in milliohms... great, until the battery in my big car died....
After I replaced it, I decided to recharge the old one and this gadget pronounced it good even though it can only sustain a 2 amp load for about 15min..... so, not sure what the algorithm is to pronounce a battery good or bad.. it sure is not reliable. I don't trust it any more and have gone back to old one that puts a 100A load on it.

I take it that you set all of the parameters (CCA, battery chemistry, etc) properly in the tester? Which one do you have? I'd like to avoid getting that one. Maybe I should also pick up a traditional 50-100A load tester too. I wonder if you had an individual cell just conk out, as opposed to the entire battery's aging process contributing to its demise.

Then again, if we look at how load testers work https://batteryuniversity.com/learn/arc ... r_readings the ones that don't draw a large current tend to rely on capacitive and inductive components inside the battery to get their readings. So I'm not sure how they could possibly get a good reading when the battery terminals are still attached to the vehicle, if there are capacitive and inductive components in the vehicle too.

[HHL]

I do have one of those testers... Also thought they are a great idea, mine even tells me what the internal resistance is in milliohms... great, until the battery in my big car died....
After I replaced it, I decided to recharge the old one and this gadget pronounced it good even though it can only sustain a 2 amp load for about 15min..... so, not sure what the algorithm is to pronounce a battery good or bad.. it sure is not reliable. I don't trust it any more and have gone back to old one that puts a 100A load on it.

I take it that you set all of the parameters (CCA, battery chemistry, etc) properly in the tester? Which one do you have? I'd like to avoid getting that one. Maybe I should also pick up a traditional 50-100A load tester too. I wonder if you had an individual cell just conk out, as opposed to the entire battery's aging process contributing to its demise.

Then again, if we look at how load testers work https://batteryuniversity.com/learn/arc ... r_readings the ones that don't draw a large current tend to rely on capacitive and inductive components inside the battery to get their readings. So I'm not sure how they could possibly get a good reading when the battery terminals are still attached to the vehicle, if there are capacitive and inductive components in the vehicle too.

The one I have is branded AutoXS. It does allow the selection of CCA capacity as well as whether it is in or out of the vehicle.

[STS134]

The one I have is branded AutoXS. It does allow the selection of CCA capacity as well as whether it is in or out of the vehicle.

What's the model number of that device? The AutoXS stuff I see doesn't even allow setting of CCA (and is more like a battery state-of-charge device and charging system tester rather than a load tester).

[Dodgemaster]

I came to the car this morning and the aux battery was flatter than a very flat thing for some reason the key does not work in the lock and the spare key is a blank so how was I going to get in to the car without the sound of breaking glass?
Fortunately not long after I purchased the car I fitted an all singing all dancing tow bar and mitsubishi electric pack. so using pin 9 (+) and an earth on the towbar brkt bolts I managed to charge the car up enough to use the fob to open it and then charge it in the usual way under the bonnet. next thing to do is find a new lock and key. I dont know whether using the car on eco at night the battery never gets a charge or what. Perhaps trying to be frugal is not a good idea for the aux battery.

[jaapv]

When you push the button on the key fob and pull out the metal loop, you'll find it is an emergency key, just for situations like this. It is set out clearly in the manual. The auxiliary battery is charged daily and when the car is running from the main battery and should never be flat. Find out why this happened. Did you leave the lights on? If you want an extra spare key, be aware that they are not cheap and must be linked to the car electronics by the dealer supplying the key. You cannot fit just any old lock and key to the car. It must be an original one and integrated in the car electronics, alarm system and ignition lock.

[AndyInOz]

In terms of consequences...

If a lead acid battery is discharged below a particular parameter (50% ?) the battery is damaged.

(Some batteries, termed 'deep cycle' batteries are able to be discharged more).

This means that the battery is probably no longer able to be fully charged.

If that has happened to your battery, it is more likely that this will happen again, because the battery has less capacity than before.

If it happens again, you'll probably have to make a judgement call about replacing the battery.

Back the in old days, after accidentally flattening a car battery, I'd find that I had to replace it within six months.

The PHEV battery only runs the electronics, so may not be as sensitive as this, i.e. doesn't have to turn an engine over with a starter motor.

[ThudnBlundr]

You want to get those metal keys sorted out. If neither opens the car, they're not the originals - someone has got some spares and got the garage to reprogram them. I had the opposite on holiday when both the key batteries were flat and I had to unlock the car using the key. The alarm went off, but putting the key in the slot and starting it turned off the alarm.

All the 12V battery has to do is start the computers and then connect the drive battery into the circuit. From then on, the DC-DC converter provides the 12V power and manages the charge of the 12V battery. So a very weak battery can soldier on until one day it fails - it's not like a regular ICE when you can hear the battery struggling to start the car on a cold day.

Best thing to do is get the battery tested properly (not just check the voltage) by using a proper tester or taking it to the garage. That wilkl tell you if it's the battery that's failed or if you've got a drain on the 12V when the car is off

[Dodgemaster]

I'm going to the auto lock shop today to get a key to fit the doors called in the agents yesterday and they are going to order the original key replacement they said about £15 and said if its not right they will absorb it. biggest problem was not being able to get in the car with a totally flat battery I wont always have a nail and my jumper to hand. Thanks for all the replies but my dodge for getting out of it might help someone in the future.

I noticed on one of the forums there was a link to a free download for a workshop manual any body seen it??

[Dodgemaster]

Can anyone tell me how to remove the lock and barrel from drivers door
locksmith told me right key wrong lock so next job is to get the barrel out cant find anything on youtube.
looking for to your thoughts
Paul