12v battery thoughts

[pollenface]

After reading some of the posts here and other places on the internet, I'm forming the opinion that there is a lot of parasitic drain on the 12v battery when the car is switched off and the car does not fully charge the battery when driving.

I've had my ZS EV for 3 months, in this time while driving (I'm always watching the power screen) I have observed it bump up the 12v battery to 14.2v for a few mins and then drop it back down to 13.8-13.6v, basically keeping it in float but never giving it a full absorption charge.

I know a lot of people on this forum are in the UK and it's probably freezing over there, knowing what I know about lead acid batteries is that they require a higher voltage charge (or temperature compensated charge) in cold weather or they will not reach 100% and will begin to sulfate and lose capacity.

What I'm suggesting is to connect an external charger to the cars' 12v battery maybe once or twice a week to give it a full temperature compensated absorption charge, hopefully that helps with the 12v battery life and reliability.

 

[N2STY]

The car chargers the battery just fine and brings up to 100% full no problem if anything it charges a lot more than an ICE car ie even when your not driving it
SOC on my 12v battery 8000 miles only ever charged by the car

 

[Kithmo]

Once or twice a week is over egging the pudding, I condition my battery twice a year, just before and just after Winter and I was beginning to think that was too much as each time I do, the battery is in a good state according to the charger/conditioner and barely takes a couple of hours to cycle through it's procedure.

 

[GVEMs]

I've had my car for almost a year and never touched the 12V battery. I parked my car in a cold airport parking, in a foreign country for a month and came back to no problem at all. I basically ticked all the risk factors and everything went fine, so I won't worry about this anymore

 

[pollenface]

Okay. Maybe I'm just getting paranoid.

 

[N2STY]

Okay. Maybe I'm just getting paranoid.

I can recommend BM6 battery monitor for peace of mind you can set a discharge limit and you can run 4 of them for multi vehicle households the app is easy to use

Battery Monitor BM6 device for Cars & Campervans 12V Battery/leisure battery tester Compatible with Android iOS and Ipad with bluetooth 4.0 and above. https://amzn.eu/d/3QMJ0sY

 

[Lovemyev]

Once or twice a week is over egging the pudding, I condition my battery twice a year, just before and just after Winter and I was beginning to think that was too much as each time I do, the battery is in a good state according to the charger/conditioner and barely takes a couple of hours to cycle through it's procedure.

Same here, I usually give it a trickle charge about once, maybe twice a year.
Not because it has flagged up any warnings, it’s just because I feel that the battery will benefit from a quick top up.
Which reminds me, our current ZS EV LR is just over 12 months old now and covered 10,000+ miles and I have not charged the 12 volt battery yet .
I have no excuses really, other than I forgot !.
The car is already fitted with a “quick connect” fly lead that is permanently
connected to the 12 volt battery, you just plug in the adapter and switch on the C.TEK smart charger unit.
Although we are retired now, our car is still used almost seven days a week and I always have the car in “ready mode” when we are making the school runs for our grand children etc.
I never have the car sitting in standby mode only, that could deplete the 12 volt battery.
I run the App once a day and just keep an eye on what the 12 volt battery status is reporting.
I also carry a 12 volt battery booster pack under the drivers seat for good measure.
Lower mileage user cases means they carry out less frequent charging of course, which also means that the 12 volt battery is receiving less charging cycles as well.
The use of 12 volt items when the car is sitting in standby mode, can be a cause of a flat battery in these low milage user cases.
The 12 volt battery in some EV’s tend to be a little smaller in capacity than what you would find in the equivalent fossil car.
One because they want to keep down the weight and secondly there is no power hungry fossil engine to crank over !.
The problem here is that there tends NOT to be a massive spare capacity in the factory spec unit.
It’s does the job just fine, if you provide it with the idea conditions and user profile.
A heavy duty battery with more capacity would be a good investment for lower mileage user case.

 

[pollenface]

I can recommend BM6 battery monitor for peace of mind

Thanks, I'll look into it.

I'm still keen to do an absorption charge on it when i get home in a few days and see how long it takes for the current to taper off.

 

[Kithmo]

Same here, I usually give it a trickle charge about once, maybe twice a year.
Not because it has flagged up any warnings, it’s just because I feel that the battery will benefit from a quick top up.
Which reminds me, our current ZS EV LR is just over 12 months old now and covered 10,000+ miles and I have not charged the 12 volt battery yet .
I have no excuses really, other than I forgot !.
The car is already fitted with a “quick connect” fly lead that is permanently
connected to the 12 volt battery, you just plug in the adapter and switch on the C.TEK smart charger unit.
Although we are retired now, our car is still used almost seven days a week and I always have the car in “ready mode” when we are making the school runs for our grand children etc.
I never have the car sitting in standby mode only, that could deplete the 12 volt battery.
I run the App once a day and just keep an eye on what the 12 volt battery status is reporting.
I also carry a 12 volt battery booster pack under the drivers seat for good measure.
Lower mileage user cases means they carry out less frequent charging of course, which also means that the 12 volt battery is receiving less charging cycles as well.
The use of 12 volt items when the car is sitting in standby mode, can be a cause of a flat battery in these low milage user cases.
The 12 volt battery in some EV’s tend to be a little smaller in capacity than what you would find in the equivalent fossil car.
One because they want to keep down the weight and secondly there is no power hungry fossil engine to crank over !.
The problem here is that there tends NOT to be a massive spare capacity in the factory spec unit.
It’s does the job just fine, if you provide it with the idea conditions and user profile.
A heavy duty battery with more capacity would be a good investment for lower mileage user case.

Pretty much the same here, CTek "comfort" connector permanently attached to the 12v, never used accessory mode when sitting in the car, always use Ready mode. 12v booster in the boot and car is used every day.
I think the 12v capacity is about right at 50 something Ah, my Gen 4 Prius only had a 40 Ah 12v and the Gen 3 only had a 30 Ah, with the same sort of charging system as the ZS, a DC to DC converter and I never had a problem with them.
My early days of motoring involved Dynamo equipped cars which put very little (if any) charge into the battery at low revs, so I was weaned on 12v battery conservation habits and continue them to this day.

 

[AK OK]

Okay. Maybe I'm just getting paranoid.

Or there's batches of cheapo batteries in & amongst failing here & there as time goes by.

Wouldn't be the first time specs are agreed, samples approved, & what turns up in bulk is almost "an interpretation" of what you thought you were getting....

 

[Alb]

I think the 12v capacity is about right at 50 something Ah, my Gen 4 Prius only had a 40 Ah 12v and the Gen 3 only had a 30 Ah, with the same sort of charging system as the ZS, a DC to DC converter and I never had a problem with them.

The MG5 is more like 64Ah IIRC.

 

[AK OK]

My early days of motoring involved Dynamo equipped cars which put very little (if any) charge into the battery at low revs, so I was weaned on 12v battery conservation habits and continue them to this day.

Go on then you tease I'll bite...

Same here, I usually give it a trickle charge about once, maybe twice a year.
Not because it has flagged up any warnings, it’s just because I feel that the battery will benefit from a quick top up.
Which reminds me, our current ZS EV LR is just over 12 months old now and covered 10,000+ miles and I have not charged the 12 volt battery yet .
I have no excuses really, other than I forgot !.
The car is already fitted with a “quick connect” fly lead that is permanently
connected to the 12 volt battery, you just plug in the adapter and switch on the C.TEK smart charger unit.
Although we are retired now, our car is still used almost seven days a week and I always have the car in “ready mode” when we are making the school runs for our grand children etc.
I never have the car sitting in standby mode only, that could deplete the 12 volt battery.
I run the App once a day and just keep an eye on what the 12 volt battery status is reporting.
I also carry a 12 volt battery booster pack under the drivers seat for good measure.
Lower mileage user cases means they carry out less frequent charging of course, which also means that the 12 volt battery is receiving less charging cycles as well.
The use of 12 volt items when the car is sitting in standby mode, can be a cause of a flat battery in these low milage user cases.
The 12 volt battery in some EV’s tend to be a little smaller in capacity than what you would find in the equivalent fossil car.
One because they want to keep down the weight and secondly there is no power hungry fossil engine to crank over !.
The problem here is that there tends NOT to be a massive spare capacity in the factory spec unit.
It’s does the job just fine, if you provide it with the idea conditions and user profile.
A heavy duty battery with more capacity would be a good investment for lower mileage user case.

Or save yourself the ££ for the bigger battery & just learn not to use anything on the car unless it's at "ready"

 

[Lovemyev]

Or save yourself the ££ for the bigger battery & just learn not to use anything on the car unless it's at "ready"

Already covered in the post above .
“Although we are retired now, our car is still used almost seven days a week and I always have the car in “ready mode” when we are making the school runs for our grand children etc” .

 

[AK OK]

Already covered in the post above .
“Although we are retired now, our car is still used almost seven days a week and I always have the car in “ready mode” when we are making the school runs for our grand children etc” .

You also said in that very same post :-

A heavy duty battery with more capacity would be a good investment for lower mileage user case.

 

[Lovemyev]

You also said in that very same post :-

Yes I did - well done 10/10 .

 

[AK OK]

Yes I did - well done 10/10 .

That's what I responded to always happy to assist

 

[Eclectic]

My early days of motoring involved Dynamo equipped cars which put very little (if any) charge into the battery at low revs, so I was weaned on 12v battery conservation habits and continue them to this day.

I used to recondition Lucas dynamos amongst other Lucas equipment, and set up the mechanical regulators on the vehicle or test bench.

I still have the special tool used to set up the slightly later current/voltage regulators, ah, the days of analogue!

 

[AK OK]

I used to recondition Lucas dynamos amongst other Lucas equipment, and set up the mechanical regulators on the vehicle or test bench.

I still have the special tool used to set up the slightly later current/voltage regulators, ah, the days of analogue!

Can't beat an old special tool

 

[Eclectic]

Can't beat an old special tool

Tell me about it!

 

[AK OK]

Tell me about it!

If you still know what you're doing with it you could be in demand in certain circles