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Ohmmu 12V Battery Feedback

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We have them in both our Model S's, I have the old BattMobile one, and my wife has the newer OHMMU battery.

I also have LiPO batteries in my daughters Ford Fusion Hybrid, and on my 10 KW generator (different brands) also have one in my alarm system.
 
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The stock battery for the Model S is 3rd party part made by C&D Technologies and AtlasBX the Model 3 & X :rolleyes: Also Magnuson-Moss Warranty Act allows you to use aftermarket parts. That doesn't mean Tesla will always do it for you, but with a battery that exceeds stock specs, and reduces the weight, it makes it easier for them and they don't have deal with you on warranty claims.

Pre Refresh Model S: C&D Tech: DCS33-UNCR. 33Ah
Post Refresh S: AtlasBX U1 AGM battery. 35Ah
Model X: AtlasBX 60B19RS. 40Ah
Model 3: AtlasBX 85B24LS 45Ah

Tesla installed my OHUMMU when I direct shipped it from OHMMU to the service center at Tyco road in Tysons VA
12 Volt Battery Compendium | TeslaTap

And yes I noticed a significant increase in my aftermarket stereo performance when pushed above 6+ to 11 on the audio dial post install of my new OHMMU battery. In fact several stereo shops use LiPo to help supply stable high demand power without adding additional weight to the car, same in the boat and RV markets.

Here's why:
4 years full-replacement warranty

Proprietary 12V Lithium cell and BMS technology that is a drop-in replacement to your existing battery (no firmware changes needed)
Battery Management System prevents damage to battery in extreme situations and also balances the battery cells to maintain the pack for longer service life!

>40Ah true Lithium capacity on 5hrs discharge test (more aggressive test than any Lead Acid test)

Easy to carry handle and only 9lbs weight

>2000 full charge/discharge cycles!


Tested in extreme climates and automotive conditions for reliability and performance.

Why go Ohmmu?

1. Increase reliability
2. Longer lasting (more life)
3. Decrease weight
4. Increase capacity
5. Increase power (no voltage sag, better 12v performance, especially for subwoofers/amplifiers)
6. Less waste (less batteries being used and less material in each battery)
7. Increase efficiency (Ohmmu 12v charges and discharges at a higher efficiency than Lead Acid/OEM)
 
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Indeed LiFePO4... read the same stories, articles, pseudo and potentially real 'scientific' info all over the interwebz.

And yet, first-hand real-life experience with this battery in place for two years in ambient temps down to 0F and up to 110F (with the car parked in ambient conditions and unplugged year round), paints a different story.

Using LiFePO4s in two family ICE and one other Tesla.
 
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Aren't they Lifepo4? How do they work below freezing? I have heard horror stories about them in the cold where the BMS would shut it off
I have had no issues with cold weather, they claim to do a lot testing and designed the battery for "extraordinary performance".

Source: https://www.ohmmu.com/battery-testing

Ohmmu Energy has invested significant time and resources into building a state of the art R&D lab where battery cell and battery assemblies are put to the ultimate test.

No other provider of these battery solutions performs the same level of OEM Tier-1 grade testing! This is why Ohmmu was selected as the first OEM Tier-1 supplier for 12V Lithium Iron Phosphate batteries.

Thermal chambers allow simulation of extreme heat and extreme cold conditions. Our in-house Thermotron chamber allows us to push the envelope with capabilities of reaching down to -70° Celsius (-94° F) on the low side and up to 185° Celsius (365° F) on the high side. Testing has been performed on all products we sell (per IEC 60068-2-1) so we can stand behind our batteries 100%.

Vibration Simulators allow us to subject batteries to IEC 60068-2-64 standardized testing, which is the OEM automotive-grade standard used to ensure longevity and durability of components. This testing subjects components to up to 60hrs of testing at frequencies between 10 and 1000 Hz. We perform vibration testing after doing temperature stress testing on batteries to ensure they are safe for operation in vehicles throughout the life of the battery.

Charge, Discharge and Cycle testing machines allow simulations of variable loads which are representative of battery conditions during operation. We have equipment which allows us to test 12V batteries with currents exceeding 100A continuously for both Charging and Discharging. To simulate life-cycles and gauge degradation rates we are able to perform continuous cycle testing which pushes batteries from 0% to 100% to 0% ad infinitum. We perform various load and cycle testing protocols during deep cold, extreme heat and vibration simulations to ensure performance in real-life applications.
 
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Any one that changed over to a Lithium 12V have any issues?
i bought the Ohhmu battery for my Performance Model 3. It worked great until there was an update from Tesla. Apparently, Tesla is aware that this battery is not OEM and through the software quarantines it. Ohmmu tells me they are working on it, but no solution yet. I bought a Tesla battery (which had i known there was a 50K warranty on and would have been free) battery for an additional $119, but feel a little taken. Ohmmu has stopped communicating with me, so i think i am out the 439 i paid, but you might want to think about that before purchasing...
 
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i bought the Ohhmu battery for my Performance Model 3. It worked great until there was an update from Tesla. Apparently, Tesla is aware that this battery is not OEM and through the software quarantines it. Ohmmu tells me they are working on it, but no solution yet. I bought a Tesla battery (which had i known there was a 50K warranty on and would have been free) battery for an additional $119, but feel a little taken. Ohmmu has stopped communicating with me, so i think i am out the 439 i paid, but you might want to think about that before purchasing...

This thing costs $439????