For All of Those Who Challenged My Stance Over the Years on OHMMU Batteries

This video does a GREAT job of summarizing the incredibly important reasons to NOT swap the OEM low-volt battery for one of these at any cost, let alone over 2.5x OEM replacement cost.

Even if you subscribe to the "benefits" this touts, none of them apply to a Tesla given the relatively nonexistent requirement for load like an ICE vehicle.

Like I said, nothing more than modern day snake oil positioned to dupe a demographic that thinks they're paying a premium for a premium product. In the end, your turn signals won't perform any better regardless of what this company tries to tell you.

Stick with OEM 12v battery replacements and invest your resources of money & time into other more important items in which you may actually find some sort of benefit. This OHMMU thing is a complete crock for Teslas though.

 

[dwbv]

I don't care much for this OHMMU battery but the video itself was very educational. Thanks for that alone!

 

[RadioZero]

awesome info, thanks for posting.

 

[kirkusss]

Finally a better explanation on what BMS really means

 

[Cosmacelf]

Thanks for posting, I hadn't gotten around to looking at that video. Ingineerx makes the best tech videos. I recommend all his other videos available on YouTube.

 

[ResHacker]

This video does a GREAT job of summarizing the incredibly important reasons to NOT swap the OEM low-volt battery for one of these at any cost, let alone over 2.5x OEM replacement cost.

Even if you subscribe to the "benefits" this touts, none of them apply to a Tesla given the relatively nonexistent requirement for load like an ICE vehicle.

Like I said, nothing more than modern day snake oil positioned to dupe a demographic that thinks they're paying a premium for a premium product. In the end, your turn signals won't perform any better regardless of what this company tries to tell you.

Stick with OEM 12v battery replacements and invest your resources of money & time into other more important items in which you may actually find some sort of benefit. This OHMMU thing is a complete crock for Teslas though.

Thanks a LOT for such input, as this video has just confirmed my initial worries when I have heard about Ohmmu or similar batteries. I have raised almost instantly questions like: ok, Li-Ion is great, but... what about freezing temps, will it heat the cells while charging? If yes, what will be the consumption of such heating, isn't it then more efficient to simply use Pb? How about BMS, does it interrupt the connection under any circumstances? As also my vacuum robot cleaner BMS does it after upgrading from NiCd to Li-Ion...!
So...really glad I have followed my concerns regarding those solutions and purchased standard AGM Pb battery.

 

[RevDrRon]

This video does a GREAT job of summarizing the incredibly important reasons to NOT swap the OEM low-volt battery for one of these at any cost, let alone over 2.5x OEM replacement cost.

Even if you subscribe to the "benefits" this touts, none of them apply to a Tesla given the relatively nonexistent requirement for load like an ICE vehicle.

Like I said, nothing more than modern day snake oil positioned to dupe a demographic that thinks they're paying a premium for a premium product. In the end, your turn signals won't perform any better regardless of what this company tries to tell you.

Stick with OEM 12v battery replacements and invest your resources of money & time into other more important items in which you may actually find some sort of benefit. This OHMMU thing is a complete crock for Teslas though.

Thanks so much for a thorough explanation of the auxiliary battery systems in Tesla. I think you also saved the life of cars and people.

 

[Droschke]

Thanks for posting this highly informative video from Ingineerix. It's unfortunate that some on this forum and on youtube keep promoting this battery over the OEM part.

 

[Ostrichsak]

Thanks so much for a thorough explanation of the auxiliary battery systems in Tesla. I think you also saved the life of cars and people.

Quick point of clarification: The video isn't mine but it succinctly and accurately outlines all of the points I've made multiple times across many threads over the years. Oftentimes I felt as though I was the sole voice of reason in a sea of insanity, so it was nice to have a little bit more evidence to support much of what I was saying that was falling on deaf ears.

Saying that it may save lives feels a bit hyperbolic, but you are correct in that the potential for catastrophe exists for people who simply think they are buying an upgrade to one of the few accessories that these cars have. Shame on the manufacturer for targeting those who don't know any better with advertising and literature that claims, this is somehow an upgrade for Tesla's.

I've called it snake oil sales multiple times, but that might be giving them too much credit for what they're actually doing and the potential harm they are placing tesla owners in by targeting them. I'm still relatively confident that several of the voices that were against me in the previous threads had some sort of a stake in the company's success. The way that others argued with obvious logic was clearly coming from a place that was more than just them taking the bait themselves and trying to justify their purchase emotionally.

 

[gt2690b]

I didn't watch the video but whats the difference in the ohmmu batteries vs. the current LFP LV batteries they are using now?

 

[Eto Demerzel]

watch the video

 

[Cosmacelf]

I didn't watch the video but whats the difference in the ohmmu batteries vs. the current LFP LV batteries they are using now?

Huge differences. The ohmmu could actually cause damage to your car.

 

[unhyphy]

I would imagine this is no different?

Vendor - Antigravity Group 51R LiFePO4 Lithium battery for Tesla Model 3/Model Y

In 18 years of tuning/performance in BMWs, we come across a number of products that fill a necessary void in the market or simply do the specific task more efficiently. Since adding Tesla to our lineup, we want to do the same and bring new and innovative products to the marketplace. While...

teslamotorsclub.com

 

[MP3Mike]

I didn't watch the video but whats the difference in the ohmmu batteries vs. the current LFP LV batteries they are using now?

Well for one Tesla isn't using an LFP LV battery. (I believe it is NCA.) For another, a lot in the car was redesigned to work with it.

 

[gt2690b]

Well for one Tesla isn't using an LFP LV battery. (I believe it is NCA.) For another, a lot in the car was redesigned to work with it.

gotcha.. apparently NMC according to this:

Tesla's New 12V Li-Ion Auxiliary Battery Has CATL Cells Inside

With the refreshed Model S/Model X, Tesla has switched from lead-acid to an all-new lithium-ion 12V auxiliary battery. Let's take a look.

insideevs.com

edit: actually Tesla is using LFP in some 12V batteries:

Tesla's new 12V Li-Ion battery dying rapidly under certain conditions - here's how to prevent it

Tesla has switched their cars to a new 12V Li-Ion battery, hoping to resolve a long-standing issue of the traditional lead acid batteries dying much faster than they typically do in internal combustion engine (ICE) […]

driveteslacanada.ca

 

[cbdream99]

Thanks for the post @Ostrichsak . I tried the Ohmmu battery fro my 2017 S last summer, and after few days I ran into the same issue as other 3/Y owners. The no response from support at all is a big red flag for me. While the owner (?) PMed me in the forum, but the conversation is more about the difficulties he is facing, at the end that's it, no resolution of any kind.

At that time I also suspect there may be other problems with my HV system and I put the original battery back, SC checked there are no issues and eventually I just ask SC to replace the 12V - cost is cheaper than ohmmu including labor. The ohmmu now is a 400 bucks paper weight. I could use that to buy 2 more Tesla 12v batteries for the next 8-10 years. It just not worth to take the risks.

 

[gt2690b]

Thanks for the post @Ostrichsak . I tried the Ohmmu battery fro my 2017 S last summer, and after few days I ran into the same issue as other 3/Y owners. The no response from support at all is a big red flag for me. While the owner (?) PMed me in the forum, but the conversation is more about the difficulties he is facing but at the end that's it. At that time I also suspect there may be other problems with my HV system and I put the original battery back, SC checked there are no issues and eventually I just ask SC to replace the 12V - cost is cheaper than ohmmu including labor. The ohmmu now is a 400 bucks paper weight. I could use that to buy 2 more Tesla 12v batteries for the next 8-10 years. It just not worth to take the risks.

it could make a good off-grid / solar powerbank for an RV maybe

 

[geordi]

So that video from the top is just blatantly negative, from someone pointing out everything they can possibly come up with that is negative.

Some counterpoints I have to offer, and bear in mind a couple things: I am a customer of Ohmmu, I bought it with my own money and it is installed in a "classic" Tesla 2016 MX. I don't have a lot of time with it so far, but here are my observations:

PRIOR to installing this, the 12v SLA battery (these are NOT AGM batteries, at least mine haven't been in two different classics so far - it is a sealed flooded battery), so the SLA had NO ERRORS popping up on the screen. But the performance was poor, I was having frequent loss of falcon door calibration, the passenger window kept losing calibrations for reasons I can't explain. The FWD speed was fairly slow.

Again, there were no errors. My drive performance power usage also seemed worse than it should be, but I haven't driven it enough since to know if that has changed yet.

I installed the Ohmmu battery, and once everything was buttoned up and booted up - I have observed that the FWD speed is MUCH faster. Even when running both at the same time, or all three power doors (rear hatch) at the same time, the speed seems to stay consistently faster. I took the opportunity to modify that ridiculous battery bucket that the car has, cutting the front wall out of that box so that the battery can be installed or removed WITHOUT taking out that metal box and risking contact with energized cables. The top clamp is more than sufficient to hold the battery in place!

The ONLY error I have observed is "cannot charge at this location" when plugging in my mobile connector, yet it starts taking power and has charged up just fine at the limit of what it is capable of. So I'm not sure what that error is about yet, it may just be something with the cable b/c it has been raining a lot, maybe there's a moisture issue.

I have opened and cycled the FWD more than a few times, lately it has been demanding calibration after about 3 cycles, so far it seems it is working great. I haven't connected my inverter again yet, so I don't know how my playstation will behave but the inverter at least can tell me what the voltage is so I know if there's an issue there. (I don't expect anything)

The video and the posts complain about the battery charging over 3.6v per cell - I don't see how that is plausible, unless the voltage is being stepped up, that is more than 14.4vdc and the DC/DC converter shouldn't ever produce that much as that would cook a FLA battery. I will monitor that. The only negative I have observed so far is a whining noise from the front of the frunk area when the car is in sleep mode - and I believe that is the coolant pump. Virtual service had previously informed me that I should have the coolant pump replaced, so I DO NOT believe that is related to the Ohmmu battery - the car doesn't know that it has a different battery, so it's either unrelated or it was on b/c it was charging the ohmmu. Don't know yet. If it is still on tomorrow, then I'll think things about it.

About the internals of the battery... Oh gee, it's made in China of Chinesium. Ya know what else is? Dang near everything. So while NO I don't like that in general, that's not a reason to not like this. The construction seems sufficient for the duties it will have to handle, carrying the computers and doors before the DC/DC powers up. The battery is NOT directly powering the power steering, and there's "no there there" about the "noise on the 12v circuits" b/c that's what every other car in history has to deal with, the alternators on everything are 3-phase generators that rectify down to 12v DC and there's PLENTY of wobbly power in those lines..... Big whoop. The computers have switching power supplies as does anything with a charger or transformer in it. They can handle it. The DC/DC is powering everything when the car is "on" anyway, not the battery.

So far I'm happy with it other than the cost, we shall see if that opinion changes. I like that things are snappier to react, so the voltage isn't sagging when stuff is being activated, which it very much WAS just yesterday. Clearly the old FLA was on the way out but the computer hadn't decided about it yet b/c the DC/DC was supplying enough to keep it just above the failure point. That's not healthy for anything!

 

[geordi]

Forgot to mention - I've already bought one battery from Tesla for the classics, and it wasn't $80, it was $165. That's ridiculously expensive for something so small. I probably could have gotten away with "rolling my own" and getting a much cheaper 12v motorsport or equipment battery like for a mower, but I didn't want to try messing about with that on my sister's car, so I paid the coin and replaced hers - ALSO having electrical issues and NOT having any warnings about the battery.

So that's two different classics with 12v batteries that were severely past their "this is how long they usually last" ages. The 2013 model S, I'm pretty sure it was the ORIGINAL 12v there. If anyone can tell me how to read the part number to get a date code, I can confirm that. The battery STILL shows 13.5 volts on my meter when it is sitting there. I might just try using it in my father's ECV as an added power source. The battery from my 2016 X, I think was a 4/2019 if the sticker on the top is to be believed. Haven't metered it yet, don't really care though. Both were the OEM batteries that Tesla uses, and I still feel this was the right call to replace it. For an average lifespan of 2-3 years though in the X... $165 does not amuse me if I can get better performance and longer life span for a bit more.

The coolant pump noise did stop tonight, so maybe that was related to the DC/DC charging up the Ohmmu. I will continue to monitor that.

 

[geordi]

The battery change did not resolve the falcon door problem, so that may be an actual mechanical issue. Who really knows, I'm only getting a calibration error and the stupid thing throwing errors that the motion was interrupted when it wasn't. The driver's door is also still acting stuck when opening, causing the ice ejector to come out once in a while.

Driving it this morning I could hear a whine from behind me when I accelerated rapidly, I don't really think that's related but it wasn't doing that before either. I actually might not have heard that b/c I wasn't driving aggressively before getting the half shafts replaced, so this could just be drive unit noise from the rear that I hadn't experienced. Possibly just me being hyper sensitive about everything right now trying to resolve these errors.

When connected to power at home, the car is saying "unable to charge" and throwing error CHG_f108... Yet is charging just fine? Haven't tried supercharger yet.