12 Volt battery is failing, I'm looking for replacement

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Looking for an AGM for the "i". I found that the dimensions on the BCI 151R sounded very familiar. They are very very close to a BCI U1 which is easy to find in an AGM. U1R with auto posts is bit more limited but I found this.

http://www.batterymart.com/p-12v-mazda-miata-battery.html

Which in my mind is perfect as an AGM replacement. It's made by east penn in the US and the price is not bad either (also on amazon). So I took a CSB U1 out of the fridge and dropped it into the car to check the fit. So far so good, so I ordered one for my "i" and in a week or so I should have it in and will report back. Basically it's shorter in height which will require a spacer of some kind under the hold down bar. A very simple mod for just about anyone.

Fingers crossed,
Aerowhatt
 
Aerowhatt said:
Looking for an AGM for the "i". I found that the dimensions on the BCI 151R sounded very familiar. They are very very close to a BCI U1 which is easy to find in an AGM. U1R with auto posts is bit more limited but I found this.

http://www.batterymart.com/p-12v-mazda-miata-battery.html

Which in my mind is perfect as an AGM replacement. It's made by east penn in the US and the price is not bad either (also on amazon).
I put one in my car a couple months ago . . . . one of my other cars is a Miata, so I've known about these batteries for years

It's a good fit, though not nearly as tall as the OEM battery. I cut a piece of pressure treated 2 x 6 the same dimensions as the battery and put that in the car and sat the little AGM on top of it. The factory hold down works fine with the battery elevated by the wood block

Don
 
I guess my dead battery was a fluke. I accidentally left a dome light on last night, and because I level 2 charged instead of level 1, the 12 volt battery had to keep power to the light nearly all night :oops: . The car didn't have any problems starting, though.

I'm still saying that the radio got stuck in a half-powered state when my battery went dead a few weeks ago. The car was started, moved, then shut back off, so the radio didn't have time to fully boot up (aftermarket Android Head unit) and thus drained the battery over two days.
 
PV1 said:
I guess my dead battery was a fluke. I accidentally left a dome light on last night, and because I level 2 charged instead of level 1, the 12 volt battery had to keep power to the light nearly all night :oops: . ...

I level 2 charge all the time. My dome light comes on initially. Then it turns off after about 10 minutes (That's a real rough estimate). If your dome light stays on all night, is there something else wrong?
 
No. I manually pushed it to turn it on, but forgot to turn it off. The door function has an auto shutoff, but not the manual on position.

The level 2 charging was only relevant because I just switched from winter to summer charging methods, and the shorter charge time means less time that the 12 volt system is powered by the converter.
 
tigger19687 said:
Holy Crap $100 !!

My F-350 batteries are only $75 each at Costco

Actually $100 for an AGM is pretty good and in the right applications (Like the "i") it has the potential to last twice, or more, as long as a standard Auto flooded battery. So with that considered it's only $50 per floody replacement. Then add in that it is nearly (if not) impossible to properly water a flooded battery where the one in the "i" is located. So it must be removed and reinstalled twice per year. All that goes away with a quality AGM. Plus an AGM will charge and discharge more efficiently. All things considered I would happily have paid $200 for it.

Aerowhatt
 
. . . . . and, the $100 AGM is actually cheaper than buying the exact replacement flooded battery which fits the car - It's a 'win-win' no matter how you score it! I typically get 7 or 8 years from the AGM in the Miata (I've had the car now for 17 years) and the OEM battery in the iMiEV lasted 3 1/2 years

Don
 
The original 12V battery in my 2012 MiEV died. I pulled it out and it was really light. I took the caps off it and it was practically dry inside. I added about 1/2 gallon of distilled water to the cells and the battery worked again!

until the next day when it only had 9 volts. i decided to replace it since it was 4+ years old, and batteries in the Desert of Nevada only last 2-3 years anyway. Also, it appeared to be leaking acid since I refilled it.

I found batteries online at Autozone and Advanced Auto Parts for $120-150. I found the 151R at Walmart for $82.22, but when I went to the store to pick it up, they are charging $117 for it there. i showed them the online price and they price matched.

It's a Everstart Maxx brand. Group size 151R with 340 CCA. It has a 5 year warranty program, free for first 3, then prorated for next 2. Walmart # 551472481

battery fit fine and all is good.
 
Before I forget, here were some recent discussions regarding our 12v batteries in a different thread (including some voltage readings):

http://myimiev.com/forum/viewtopic.php?p=29784#p29784

Here's a link to a more-detailed discussion of our i-MiEV 12v battery:

http://myimiev.com/forum/viewtopic.php?f=23&t=3067

For those of you seeking to replace your 12v battery with Lithium, here's a recent discussion on Teslarati ... with their surplus of 18650-format cells, I have to wonder why Tesla has not gone this route. :?: :geek:

http://www.teslarati.com/why-tesla-12v-battery-needs-to-be-lithium-ion/

Here's an outfit undertaking the 12v replacement market with Lithiums - rather pricy IMO and no product yet:

http://www.battmobilebatteries.com/

For the time being I am keeping my Tesla 12v AGM battery continuously on a float charger as the car normally sits in the garage under cover and is used only for long trips.

I'm watching my original 2012 i-MiEV 12v batteries gracefully degrade. If my i-MiEVs are not going to be used for even a few days I now attach a float charger to each of them. If I kept my i-MiEV outdoors, I would attach a small solar panel and regulator to it.

When the time comes, I'll be replacing my i-MiEV flooded-lead-acid with a very small AGM - perhaps an Odyssey as they like a bit higher charging voltage than the usual (e.g., Deka) AGMs.
 
So, we called the Mitsubishi dealer about a 12 volt battery replacement. They want $198. Advance Auto Parts has one for $139, but when talking to the guy, he said that it couldn't be changed by just anybody because they have to wear a suit and stand on an insulated pad. He knows someone that was killed by changing one of these "hybrid" batteries. I'm tempted to stop in and see if he'll change it anyway if I don't tell him what kind of car it is.

:roll: More mis-information holding back the rEVolution, regardless of the fact that our cars de-energize the high-voltage system when it's off and not charging. Guess I'll just put four LiFePO4 pouch cells that I have lying around in a watertight box and hook them up.

(If I could get a drive battery for $139, I'd have a whole garage full of them :mrgreen: .)
 
Found my power drain. Apparently, my OBDLink doesn't like going into sleep mode. I haven't touched the car all weekend, but the OBDLink is still actively broadcasting Bluetooth availability. I have it placed so the lights are visible outside the car. I just pinged OVMS with a Diag? message and it returned 7.6 volts on the 12 volt system.
 
PV1 said:
Found my power drain. Apparently, my OBDLink doesn't like going into sleep mode...7.6 volts on the 12 volt system.
:shock: Forgot about that one! Thanks for pointing this out, as I never remove my OBDLink. Presumably you successfully recharged the battery with an external source.

As I'm away, I've left each of my i-MiEVs sitting on a Battery Tender float charger, so should be ok when I get home, but before I disconnect I'll put an ammeter on each charger to see how much it's feeding the car, as it will have been sitting that way for a few weeks and should be well stabilized.
 
It's on the charger now. It was interesting jumping it this time. I started charging the battery, opened the door, then had the headlight relays start clicking on and off. I turned the charger off, but it continued. I turned it back on, but turned up the amps, and as the headlights started flashing, the horn started beeping. The alarm was going off :lol: . I hit the Unlock button on the remote and it stops. Apparently the alarm will stay armed even if the battery goes near dead.

One of these days I'll eventually replace the battery ;) .
 
From another thread -
twiin640 said:
I replaced my original with an Optima yellow top.
$$$ouch! I have over a dozen Optima D34 lying around here (left over from my Sparrows), but haven't yet needed to replace my i-MiEV OEM so haven't even tried to see if they fit. Exactly which Optima yellow-top did you install and did you need to make any mods to make it fit? I thought we already discussed this somewhere on this forum, but I couldn't find it.
 
Any AGM advertised as being a replacement for a '90 to '97 Miata (they all came from the factory with an AGM mounted in the trunk) is a good replacement for our cars and you can usually find one for about $100, many times with free shipping. The AGM is a little shorter than our battery, but if you cut a piece of 2 X 6 the same size as the bottom of the battery and mount it under the battery, the factory hold down works fine and you don't need to change anything. A much better battery than our flooded one and cheaper to boot!

Don
 
JoeS said:
From another thread -
twiin640 said:
I replaced my original with an Optima yellow top.
$$$ouch! I have over a dozen Optima D34 lying around here (left over from my Sparrows), but haven't yet needed to replace my i-MiEV OEM so haven't even tried to see if they fit. Exactly which Optima yellow-top did you install and did you need to make any mods to make it fit? I thought we already discussed this somewhere on this forum, but I couldn't find it.

I apologize for the delay, busy summer and I haven't been on this site in a while. Anyhoo, I'm fairly certain you've already sourced another battery by now but you asked which one I used so I'd like to pass that info.

Optima Yellow Top D51R. It fits nicely but the Optima is too wide for the plastic battery tray in the vehicle. You can either totally remove the plastic battery tray or modify it so that the battery will "sit" on it correctly. I cut off the ends of the tray so that now the ends have no lip. The battery now sits flat on the plastic tray. It's been a while but I also think the Optima also has more capacity and CCA than the OEM. If you need more info please email me directly.
 
my plan is to go cheap, since i don't think there is very much demand on the 12v battery.

https://www.harborfreight.com/12-volt-35-amp-hour-universal-battery-68680.html

$70 at HFreight (less the usual 20% coupon). I've used these on numerous Prius.

Is there any reason this 35Ah 12v wouldn't work in the i ?

thanks
 
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