12v Battery Recommendations

[LeftieBiker]

So if EV is used daily extra capacity has zero effect on battery longetivity.

Two points:

* Many EVs are not used daily, and some not even weekly.

* There is anecdotal evidence that the Leaf does a better job of charging higher capacity lead batteries than it does lower capacity lead batteries.

[Stanton]

* There is anecdotal evidence that the Leaf does a better job of charging higher capacity lead batteries than it does lower capacity lead batteries.

But they do the best job of charging LiFePO4 12v batteries
At the end of the day, you can't "fix" the inherent problems of Lead Acid batteries...and there are many more (good) Lithium options now than when I installed my LiFePO4 12v over 5 years ago.

[LeftieBiker]

* There is anecdotal evidence that the Leaf does a better job of charging higher capacity lead batteries than it does lower capacity lead batteries.

But they do the best job of charging LiFePO4 12v batteries
At the end of the day, you can't "fix" the inherent problems of Lead Acid batteries...and there are many more (good) Lithium options now than when I installed my LiFePO4 12v over 5 years ago.

I assume that this is because lithium batteries have a charging profile that fits the Leaf's charging algorithm well. Since better AGM batteries also work, and cost much less, that's the route I suggest for most people. The Leaf may well have been initially designed for a lithium accessory battery. We can at least be fairly sure that it wasn't designed to sue a cheap little starting battery.

[Gigawatt]

I have a $5000 2012 leaf with 60k and all 12 bars. I've been chasing down a parasitic drain for last 6 months, finally changed to a new (From Costco %80) Lead acid battery that seem to work fine at first but now with the cold weather for the past two months it goes dead after a few days. Putting a multimeter on the batter gives me only about 10.5 volts after 6h or driving the car. After messing about with an ammeter it seems to be a bit better now.

• I've had the battery load tested - seemed OK.

• I've attached an Ammeter looked at the supposed set of relays that seem to pull excess current - got standby the amperage down a bit by swapping two identical relays with each other!

• I have trickle charge it and this seems to work but it's a pain to keep opening the hood - I did have a lead that I thread to the out side of the car at one stage

• The new battery did get really flat a few times and I noticed that the plates on the last cell were really empty of electrolyte and looked a little pitted so perhaps the battery is toast even if the load test says otherwise?

So what are my options?

Nissan wants $300 just to diagnose it. I could put in a Yellow top but they seem to be crap quality. I am game to put in a bigger capacity lead acid battery. Would even consider a 12V LiFePO4 up to $200 but what brand / mode to buy? It would be nice to find the issue though!

[lorenfb]

I have a $5000 2012 leaf with 60k and all 12 bars. I've been chasing down a parasitic drain for last 6 months, finally changed to a new (From Costco %80) Lead acid battery that seem to work fine at first but now with the cold weather for the past two months it goes dead after a few days. Putting a multimeter on the batter gives me only about 10.5 volts after 6h or driving the car. After messing about with an ammeter it seems to be a bit better now.

• I've had the battery load tested - seemed OK.

• I've attached an Ammeter looked at the supposed set of relays that seem to pull excess current - got standby the amperage down a bit by swapping two identical relays with each other!

• I have trickle charge it and this seems to work but it's a pain to keep opening the hood - I did have a lead that I thread to the out side of the car at one stage

• The new battery did get really flat a few times and I noticed that the plates on the last cell were really empty of electrolyte and looked a little pitted so perhaps the battery is toast even if the load test says otherwise?

So what are my options?

Nissan wants $300 just to diagnose it. I could put in a Yellow top but they seem to be crap quality. I am game to put in a bigger capacity lead acid battery. Would even consider a 12V LiFePO4 up to $200 but what brand / mode to buy? It would be nice to find the issue though!

What is the actual current measurement? It should be less than 100ma, typically around 25-50ma.
For a very basic calculation of a time period without charging and to be able to "start" the Leaf:

Assume a 50Ahr battery rating at 1/2 capacity & 100ma (.10 amps);

Time (days) = 50Ahr/2/.10amps/24hrs ~= 10days, Obviously less for the typical small Leaf battery rating used.

[Gigawatt]

Pretty sure it was at least more than 100mA (200mA I think) and yes I concur it will drain the battery quickly at that rate. I can check when it warms up a bit.

[GerryAZ]

I suspect something is keeping the car from going into "sleep" mode so the residual current from the 12V battery is higher than normal. On top of that, 2011 and 2012 models only turn on the DC-DC converter for 5 minutes every 5 days when parked and they will not initiate the 5-minute charge (or 5-day timing cycle for charging) if the car does not go to sleep. This makes them more prone to deeply discharging their 12V batteries. I personally left my 2011 parked for extended time without issue except for the one time I forgot to unplug the Bluetooth adapter from the OBDII port and left an Android device running Leaf Spy on the passenger seat. I came back to a completely dead 12V battery after only 6 days. Although I replaced it before it drained the battery too far, I had the little relay which powers the electric shift control module stick in the energized position a few times. The increased residual current to keep that module energized would have drained the 12V battery if the car were parked for more than a couple of days.

Check to make sure that all doors and the hatch are securely closed when parking. Also, unplug device(s) plugged into the OBDII port when parking for more than a day or two. If you can measure excessive discharge current with an accurate ammeter, you can try pulling one fuse at a time until you find the circuit which is drawing too much current.

[SageBrush]

As of mid 2020, Toyota is outfitting its 'harrier' (Venza) hybrid with "Li" batteries from Yuasa. I am guessing that these are LiFP since the spec has charge/discharge down to minus 30C. That model has a 1500 watt, 120 volt accessory port, which I presume is the reason to outfit the car with a deep cycle, LiFP battery.

If I can find the battery for sale locally I'll look more into its specs

[Gigawatt]

I did the Ammeter / fuse removal thing and didn't see that any circuit was the culprit really. Perhaps I'll give it another try. I have all interior light replaced with LED bulbs and I turn them all off when doing the test.

What should the 12v batter read voltage wise, my batter sits around 10.5v, climbs to 14 when charing by leaf. Perhaps a dead cell. It should read 12.6v right after turning the car off.

[LeftieBiker]

10.5 volts is essentially a dead battery. I'm surprised that the car works.