Amazon battery source for i3 12v battery

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merkurmaniac

Member
Joined
Oct 15, 2017
Messages
12
My son's away at college, and when the time came for him to come home for the holiday's, the car suffered a stroke. Couldn't charge, warnings about battery discharging while sitting, car was dead. REX would not come one. He got a ride back to Houston from A&M and we figured out it was probably the Penn Deka battery I had bought that had now gave up the ghost. It was 2 years, 10 months old. Dissappinting.

Autozone had nothing in their system, nor advance autoparts, nor OReilley's Batteries Plus listed some junky small batteries that looked like something for JetSkis. I left a message with BMW parts in College Station who replied with a cost of $253 and a transit time of 2 weeks from Germany. Amazon had an "energizer" brand for $107, free 2 day shipping. That beats ordering another thru PennDeka and paying shipping, which would have ended up around $185 plus who knows when delivery.

The battery I got was : https://www.amazon.com/dp/B07CR4JTZR?psc=1&ref=ppx_yo2ov_dt_b_product_details and carried a warning that it DOES NOT FIT my 2015 i3. A review said it does, and the review was right. Its a 21AH battery, the original is 20AH. Same physical size. There is some chatter about having to buy SAE brass tall extension posts or something that has to be hacksawn, but that's not the case. It comes with a few screws, spacers, and square nuts. Use the square nuts and it fits.

I guess I register it this time. Last time I talked myself into not needing to , since it was the same, etc... less than 3 years life sucks, tho. I'll buy the bimmerlink app and have a go at registering it. It was amazing the drunken stupor the car was in after we changed the battery. It took an hour on the slow charger for the REX to fire up and things to get back to normal. I was scared I'd have to tow it to the dealer and pay who know how much to do who knows what to the car.

All good now, from what I can tell.
Richard



Amazon description in case the hyperlink dies : "Energizer TX24HL AGM Motorcycle and ATV 12V Battery, 350 Cold Cranking Amps and 21 Ahr, Replaces: YTX24HL-BS and others, Black"
 
interesting that the OEM terminal connectors fit without having to hack them. Normally this is an issue with the plastic casing that does not allow the same amount of room for the bulky adapters to fit but perhaps this one is slightly different.

Also- Three years is an expected life span for an AGM battery in a hot climate and I see you are in Texas. I don't think spending extra money to "Register" it is going to help the battery last longer but do what makes you comfortable.
 
merkurmaniac said:
Autozone had nothing in their system, nor advance autoparts, nor OReilley's Batteries Plus listed some junky small batteries that looked like something for JetSkis.
For what it's worth, Carquest Auto Parts stores in Hawaii sell the Deka AUX18L for $142 and claims to be able to get one within 1 or 2 days. This is identical to the original i3 battery, just relabeled. Carquest has stores scattered around Texas as well.

What you bought from Amazon is a power sports battery (i.e., for a jet ski, motorcycle, or other application in which the battery isn't in a confined space). The problem that I have with a power sports battery is that their cells aren't vented to a common vent pipe like the original battery. Because of this, any gasses that are vented won't be directed down the vent tube to below an i3 but could accumulate in the frunk. This would occur only when a battery is failing in a certain way which probably isn't very likely. However, a recent post in this forum described just such a failure mode in which flammable hydrogen sulfide was vented. No explosion occurred, but it could have.

merkurmaniac said:
I guess I register it this time. Last time I talked myself into not needing to , since it was the same, etc... less than 3 years life sucks, tho. I'll buy the bimmerlink app and have a go at registering it.
I think the cost of BimmerLink plus an OBD to WiFi or Bluetooth adapter is worthwhile in general, but probably not for just registering a battery. If registration really does increase the life expectancy of the battery, the cost of BimmerLink and an adapter would almost certainly be more than the savings from an additional few months of battery life. A BMW certified i mechanic who owns an i3 says that registration of an i3 battery does nothing more than record its installation date, battery type, and capacity unlike with BMW ICE vehicles in which registration also changes the behavior of the alternator to decrease fuel consumption and to charge the battery according to its age and condition.
 
Interesting about the registering thing. I already have the bluetooth OBII dongle and bimmercode, but I think bimmerlink is another $30. I'll probably split that with a friend with whom I replaced the battery last time around. He actually was telling me he was thinking about replacing his again, so my son's stranding would be a warning, perhaps. I am kindof suspiscious of the idea that the car recharges the battery somehow differently as it ages, it just doesn't make much sense. I am considering fitting the old bmw i3 battery to my riding mower if it will fit in the box. I keep it on a tender in the garage mostly anyways. Curious to see how it performs, even tho it's "bad."

I can't get too exited about the venting of the battery. On my older 525, it was under the seat in the passenger cabin. This one, is under the hood, like any other car's battery, plus that tube goes where... down somewhere under the hood. It's not like anything up there is air-tight, judging by the bushel of leaves that were in the frunk box.
 
EvanstonI3 said:
interesting that the OEM terminal connectors fit without having to hack them. Normally this is an issue with the plastic casing that does not allow the same amount of room for the bulky adapters to fit but perhaps this one is slightly different.

I was wondering about what the interference was. It comes with a variety of screws, cylindrical spacers, and square nuts. I just fitted the square nut into the battery post box thing and was able to fit the big brass terminal adapters directly to the battery using the original Torx bolts. I dunno if later vintages of the i3 have a different battery post assembly or not.

This battery does have a single sort of vent hole in the back center of the battery, but my son could not get the plastic elbow to fit into it, so perhaps it was a dummy hole. I always just suspected that the vent tube on my old 525 was really just to prevent corrosion of nearby metal surfaces from whatever acidic stuff was in any battery fumes. I am kinda surprised that the i3 has tubing, since it's a more conventional spot under the hood rather than the trunk or under the back seat.
 
merkurmaniac said:
I was wondering about what the interference was.

The square posts are not the issue, it seems to be that the CASING is molded differently in other batteries, so people either have to buy simpler looking adapters to put on the posts or they hack away at the OEM post adapter so it looks like this:

GQFMUdk.jpg


here is an OEM battery w/ OEM post adapters on the Right and another AGM power sport battery on the Left with the different post adapters installed:

jT8t7zy.jpg
 
agzand said:
The OEM battery is Remi:
Small nit: the original battery is manufactured by East Penn Manufacturing. Remi just relabels this battery as do BMW and Deka (well, Deka might be East Penn Manufacturing's retail brand).
 
EvanstonI3 said:
interesting that the OEM terminal connectors fit without having to hack them. Normally this is an issue with the plastic casing that does not allow the same amount of room for the bulky adapters to fit but perhaps this one is slightly different.

Also- Three years is an expected life span for an AGM battery in a hot climate and I see you are in Texas. I don't think spending extra money to "Register" it is going to help the battery last longer but do what makes you comfortable.

Here in the Pacific Northwest, my OEM 12V battery lasted eight years, but in retrospect there were warning signs for several years prior: momentary power steering failures, "drivetrain malfunction" messages, etc.

When I was replacing my 12V battery, I noted the terminal clamps weren't loose, but could be easily rotated around the posts. Ambient temperature was in the 40's, so the tightness would be different on a hot day. If the tightness were to get just an eensy bit looser the electrical resistance could increase. That increased resistance would limit charging currents and hamper algorithms meant to reduce sulfation effects (which shorten battery life).

So, I have a couple takeaways from my experience:
1) If my car bricks away from home, give the battery connectors a twist before calling to have the car towed away ($$).
2) Seasonally check that the terminals are snug (won't twist in place), and have a wrench ready to tighten then down.

BMW chose to insert an adapter/interposer between the battery terminals and the clamps. That adapter is a dissimilar metal (brass, bronze?) with significantly different hardness and thermal expansion - doomed to come loose over time IMHO.
 
Just installed an Energizer TX24HL battery from Amazon. The BMW terminals from the old battery swap over perfectly. I can also confirm that this battery does have a vent hole in back. The interior of the vent hole becomes a bit narrower towards the interior of the battery and as a result this area is slightly too shallow to fit the factory vent hose nipple, so I tapped it very slightly with a drill bit and the hose nipple fit in perfectly afterwards. Be very careful if you do this because you can see the battery plates inside the hole and you don't want to go too far and hit them. You're only drilling out a couple of millimeters. Alternatively, you could probably find a smaller nipple or glue the factory nipple in place.

On a related note: The factory battery was still in my 2017 rex and I haven't had any issues with it. It's dated 45/16, so it's over seven years old. After pulling it, I measured the voltage at 12.94V. So I guess some of these batteries can last quite a while. This one has spent its life between northern California and Philadelphia.
 

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Here in the Pacific Northwest, my OEM 12V battery lasted eight years, but in retrospect there were warning signs for several years prior: momentary power steering failures, "drivetrain malfunction" messages, etc.
Momentary electric power steering (EPS) failures aren't caused by a weak 12 V battery but by a bug in the EPS software. BMW will update the system software to fix this problem at no cost within 10 years of the in-service date for i3's driven less than 120k miles according to this Service Information Bulletin:
SIB 32 11 19 STEERING ASSISTANCE SPORADIC REDUCTION: EPS SOFTWARE UPDATE EXT LTD WTY COVERAGE.

I doubt that drivetrain malfunction errors would be caused by a weak 12 V battery because the drivetrain components are all high-voltage components.
2) Seasonally check that the terminals are snug (won't twist in place), and have a wrench ready to tighten then down.
This is good advice. However, you'd need 2 wrenches: a 10 mm wrench to tighten the terminal clamps and a Torx wrench (T-25??) to tighten the attachment screws for the SAE posts. Either could be loose which would allow the clamps to rotate which could cause troublesome power interruptions.
 
In retrospect, I wish I had added some threadlocker to the torx screws that hold the SAE posts down.
 
Just installed an Energizer TX24HL battery from Amazon. The BMW terminals from the old battery swap over perfectly. I can also confirm that this battery does have a vent hole in back. The interior of the vent hole becomes a bit narrower towards the interior of the battery and as a result this area is slightly too shallow to fit the factory vent hose nipple, so I tapped it very slightly with a drill bit and the hose nipple fit in perfectly afterwards. Be very careful if you do this because you can see the battery plates inside the hole and you don't want to go too far and hit them. You're only drilling out a couple of millimeters. Alternatively, you could probably find a smaller nipple or glue the factory nipple in place.

On a related note: The factory battery was still in my 2017 rex and I haven't had any issues with it. It's dated 45/16, so it's over seven years old. After pulling it, I measured the voltage at 12.94V. So I guess some of these batteries can last quite a while. This one has spent its life between northern California and Philadelphia.
I just did the same thing you did and order the TX24HL from Amazon. It was sort of a "just in case" thing as my battery is only 3 years old and showing no signs yet of failure. Although on a GM I had, (no more GM vehicles for me, BTW) its Delco battery failed without warning after 3 years. So I figure to by the Amazon battery, smart charge it, and keep it on standby in the garage.

Thanks for the tip on the battery vent hole. I saw those different sized nipples at the hardware store. Also another tip I learned was to cover the terminals with some hi-temp wheel bearing grease to prevent corrosion.
 
i havea bluetooth Voltage monitor on my 12V battery
after 5 yrs, the voltage is now starting to drop significantly when cold, did not do so last year
new one will be fitted shortly
 
Just installed an Energizer TX24HL battery from Amazon. The BMW terminals from the old battery swap over perfectly. I can also confirm that this battery does have a vent hole in back. The interior of the vent hole becomes a bit narrower towards the interior of the battery and as a result this area is slightly too shallow to fit the factory vent hose nipple, so I tapped it very slightly with a drill bit and the hose nipple fit in perfectly afterwards. Be very careful if you do this because you can see the battery plates inside the hole and you don't want to go too far and hit them. You're only drilling out a couple of millimeters. Alternatively, you could probably find a smaller nipple or glue the factory nipple in place.

On a related note: The factory battery was still in my 2017 rex and I haven't had any issues with it. It's dated 45/16, so it's over seven years old. After pulling it, I measured the voltage at 12.94V. So I guess some of these batteries can last quite a while. This one has spent its life between northern California and Philadelphia.
You are a brave soul! Messing even with the BMW 12-Volt battery / setup had severe consequences for me. Maybe coincidence though and underlying issues. Please keep us all posted how this works for you. BTW, you have a 2017 i3 REX? Same here. Just spent $5K on new transmission and $3.5 K on new high voltage regulator module that handles REX charging and DC fast charging.
 
You are a brave soul! Messing even with the BMW 12-Volt battery / setup had severe consequences for me.
If you are thinking that had anything to do with your "HV regulator module", that is highly unlikely, though it's unclear to me which device that is. The only big risk I am aware of with 12V system shenanigans is the potential to short out the output of the DC-DC converter if powered up, but I suspect even that is fused or breakered in a way that can be fixed or reset.

I'm currently testing one of these lithium batteries with SAE post adapters, and after a month, it is holding up well. At $65, it's a relatively inexpensive risk for a lithium pack with thermal charge regulation.
 
If you are thinking that had anything to do with your "HV regulator module", that is highly unlikely, though it's unclear to me which device that is. The only big risk I am aware of with 12V system shenanigans is the potential to short out the output of the DC-DC converter if powered up, but I suspect even that is fused or breakered in a way that can be fixed or reset.

I'm currently testing one of these lithium batteries with SAE post adapters, and after a month, it is holding up well. At $65, it's a relatively inexpensive risk for a lithium pack with thermal charge regulation.
I'm also testing a LFP battery in our 2019 U.S. i3. The model that I'm testing is considerably more expensive than your Moseworth battery, but it does include a Bluetooth radio that communicates with a smartphone with an app that displays quite a bit of information about the current battery state and supports turning off charging and/or discharging.

The height of the Moseworth battery is ~0.2" taller than the OEM battery just as the LFP battery that I installed. To be able to install the battery hold-down bracket, I had to remove the pad on the underside of the top horizontal section of this bracket. I stuck this pad on the inside of vertical section to tighten up the fit for this battery that's not as thick as the OEM battery. Did you have similar fit problems?
 
I can report success with a much more expensive ($120 shipped to door). Duralast AGM Ready-To-Ride Power Sport Battery ETX18L 340 CCA plus <$20 shipped for the XS POWER BATTERIES 580 SAE SHORT BRASS POST ADAPTERS M6 THREAD XSPOWER TERMINALS.

Note: The negative and positive terminals are different diameters, make sure you put them on the correct side of the battery.
 
I can report success with a much more expensive ($120 shipped to door). Duralast AGM Ready-To-Ride Power Sport Battery ETX18L 340 CCA plus <$20 shipped for the XS POWER BATTERIES 580 SAE SHORT BRASS POST ADAPTERS M6 THREAD XSPOWER TERMINALS.

Note: The negative and positive terminals are different diameters, make sure you put them on the correct side of the battery.
Good job !! My local Autozone had those batteries on the shelf for about $120 after the core. But I couldn't figure out how I was going to hook up the terminals. Now I know !!

Good to know a store has them on the shelf for emergencies instead of going to the BMW stealership and paying their price.
 
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