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Zoe Devotee
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9,215 Posts
Wow all that work to identify an incorrect spec battery. Poor owner must have been having kittens at a possible £xxxx repair bill and all it took was the right battery.
 
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I'm not crazy, the attack has begun.
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29,241 Posts
Worse still is that over 10 years since the frist BEVs, and 20 years since Prius' and the like, EVERYONE should now know that 12V batteries are a big weak, undiagnosable point.

Why does it take 2 decades of experiences that we are STILL at the point that 12V battery faults are still going undiagnosed and not properly prognosed (is that a word?) in normal BEV setups.

I have advocated for almost 8 years now; EVERYONE get a cheap battery volt reader and superglue* it into your accessory socket. Keep an eye on it during startup, driving around, etc, get used to what it SHOULD say and when it isn't saying those things then know your battery is not doing well.

EVERYONE. RIGHT NOW. JUST DO IT. A QUID OR SO OFF EBAY. BUY IT. NOW. STOP SITTING THERE DRINKING YOUR COFFEE. NOW. EBAY. £1 PLUG IN VOLT METER. JUST DO IT. NOW.

:)

If you only ever follow one piece of my advice, follow that one.

*(Obviously I mean 'just leave it there forever', you don't have to take it literally, unless you really want to! ;) )
 

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KIA Soul EV 64kWh
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179 Posts
Worse still is that over 10 years since the frist BEVs, and 20 years since Prius' and the like, EVERYONE should now know that 12V batteries are a big weak, undiagnosable point.

Why does it take 2 decades of experiences that we are STILL at the point that 12V battery faults are still going undiagnosed and not properly prognosed (is that a word?) in normal BEV setups.

I have advocated for almost 8 years now; EVERYONE get a cheap battery volt reader and superglue* it into your accessory socket. Keep an eye on it during startup, driving around, etc, get used to what it SHOULD say and when it isn't saying those things then know your battery is not doing well.

EVERYONE. RIGHT NOW. JUST DO IT. A QUID OR SO OFF EBAY. BUY IT. NOW. STOP SITTING THERE DRINKING YOUR COFFEE. NOW. EBAY. £1 PLUG IN VOLT METER. JUST DO IT. NOW.

:)

If you only ever follow one piece of my advice, follow that one.

*(Obviously I mean 'just leave it there forever', you don't have to take it literally, unless you really want to! ;) )
Prompted by this post I took some 12V battery readings today on my KIA Soul EV 4kWh.
Battery = 12.3V mode = OFF
Battery = 12.22V mode = ACC (DLR & Radio on)
Battery = 14.75 mode = ON/READY
The last reading seems a bit high, I expected 14.4V for the sealed flooded battery.
Is this normal?
 

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I'm not crazy, the attack has begun.
Joined
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29,241 Posts
Prompted by this post I took some 12V battery readings today on my KIA Soul EV 4kWh.
Battery = 12.3V mode = OFF
Battery = 12.22V mode = ACC (DLR & Radio on)
Battery = 14.75 mode = ON/READY
The last reading seems a bit high, I expected 14.4V for the sealed flooded battery.
Is this normal?
Ye it is normal at start up, on mine it usually read 14.4V during running, but on start up it is usually more. This would be the norm for AGM and sealed batteries, but you are right to point out it is a flooded cell battery fitted as standard. It doesn't hurt a flooded cell for a brief moment, and will still serve a purpose to reduce long-term sulphation. The Soul would sometimes back off to 13.6V but was at 14.4V longer than other EVs I have seen (i.e. is looking after its battery better).

The Zoe is running routinely at 13.3V. This is too low for good battery health, AFAIK. There is a minimum 'float' voltage which is the point where the battery can form part of an electric circuit and is neither under electrical stress in either charge or discharge cycles.

For electrochemical reasons, due to wonderful things like "pseudo-capacitance" and such, an open circuit battery voltage may find a level which differs to the electropotential that is most stable for the cell chemistry (i.e. if free ions are present and passing back and forth).

Some of this detail is slightly 'black-art' so is more based on my experience than strict research, and a lot of it is not even known any more to even look up .. I have an old book from the 1960s with a lot more detail in it about lead acid chemistry than anything you can find today. It's sort of funny how hard-won engineering knowledge seems to get 'lost' and has to be rediscovered. Have respect for old books ... ;), they often contain stuff that has been forgotten already.
 

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KIA Soul EV 64kWh
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179 Posts
Donald thanks, good to know that the battery maintenance voltage is adjusted during the charge cycle.
As you say, the SOC & SOH are hard to obtain from open circuit terminal voltage. I used to have an hydrometer to measure specific gravity of the electrolyte!
Agree about lost knowledge, same with other tech eg. Superregen & superhet RF demodulation techniques!
 

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Zoe ZE40 R90
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524 Posts
Some of this detail is slightly 'black-art' so is more based on my experience than strict research, and a lot of it is not even known any more to even look up .. I have an old book from the 1960s with a lot more detail in it about lead acid chemistry than anything you can find today. It's sort of funny how hard-won engineering knowledge seems to get 'lost' and has to be rediscovered. Have respect for old books ... ;), they often contain stuff that has been forgotten already.
Very true. I started in the motor trade in 1966, and one of my first jobs was learning how to fill, charge and commission lead/acid batteries. At that time we could also remove faulty cells and replace them (the equipment looked like medieval torture instruments!) This was usually done on the large, expensive agricultural and commercial batteries.

As I progressed, I learned how to repair and set up control boxes (analogue/mechanical coil with points)
Voltage control units were superceded by current control boxes, with two sets of points and different settings to match the output of the fitted dynamo.

Everything was made and set up to benefit the battery, but needed regular maintenance. I still have the setting tools rusting quietly in my old tool box.

Pretty much all gone and forgotten now, yet lead/acid batteries are still very much with us.
 

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Co-author of CanZE. Q210 nov 2013
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4,450 Posts
Maybe a good reminder that Renault recommends replacing the 12 V battery every 3 years. Many people, of course including on this forum scream foul when presented by this advice 1) , but it's not a complicated proposition: if you are handy and can replace the battery DIY, there is no reason whatsoever to do it after 3 years. You can even bootstrap ZOE to drive to that battery shop 2). If you are not, follow the bloody advice. Yours truly kindly declined and replaced it 5.5 years in after the car was throwing an error once it got colder. After two horrific sub 8 volt drains, but why that happened is another story. It was a no brainer to do so.

What is a pity at best, and telling at worst, is that the above linked story did not say how old the car/battery was...... And that they were not using CLIP but generic tools. Though I agree wholeheartedly that the bloody thing should display: "12 volt bus low, replace battery" with a few disclaimers.

1) No, this advice is NOT to fill the coffers of the Renault dealership. It's to avoid you getting stuck with a dead battery and then screaming foul, including on this forum, that how on earth could an ELECTRIC car go dead on an almost brand new, just 4 years old, 100 years old tech lead acid battery. Rock, hard place, can never do right. Sigh. Personally, my only beef with the dealership was that they wanted to charge me way too much for a new battery, from memory 175 euro. Got me a Varta c22 for 69 euro and putting it in was a 15 minutes jobby. Have it done by your under-the-arches if needs to be.

2) Yes, I know, the instruction manual says it's highly prohibited, yap, yap. It works. And my friendly Renault mechanic told me to do so. Yes I know, had I blown up something he would not have taken blame.
 

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I'm not crazy, the attack has begun.
Joined
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29,241 Posts
.... 1) , but it's not a complicated proposition: if you are handy and can replace the battery DIY, there is no reason whatsoever to do it after 3 years.
I think you meant 'not to do it', but in any case there is a good reason not to do it; replacing a perfectly serviceable lead acid battery is wasteful.

At least they are largely recycled very efficiently, but the expenditure of energy and waste in its remanufacture is not desirable, environmentally.

And all that needs to be done is just to keep an eye on the volts showing on your volt readout, and spot when it is beginning to go awry.

Lead acid batteries are SOOO non-digital, they will give you months of warning they are going to go phfffut. The problem is that if you in a BEV and are not cranking an ICE over on startup - "chug, chug chuuuuug, chuuuuuuuuuuggg, brrrrum..." - you don't get the hint UNLESS you are watching your voltmeter, which you should have anyway because even perfect batteries can be killed by a less-than-thoughtful 12V battery management algorithm on your car.

But do as you please; give to the environment with one hand and take away from it with the other. Not at all hypocritical, no, no, not at aaaaallllll .......
 
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