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Lithium 12v battery upgrade question

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Any concern about the Ohmmu not having a BMS (compared to the MPP)?
Where did you get that information from? Here is directly from their website:

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 11lbs weight
 
Where did you get that information from? Here is directly from their website:

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 11lbs weight

Looks like I didn't read far enough...thanks for the feedback!
 
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Looks like I didn't read far enough...thanks for the feedback!

No worries, I've had mine for 15 months now and it's been perfect. No voltage sag an holds higher rate of charge for much longer compared to OEM. I am fortunate as I've never seen any error like some have, but Ohmmu is releasing rev 2 on October 12th and has notified all existing owners that they will do a free swap to the new version for no cost. That is excellent customer service. it already includes a 4 year warranty anyway, but this can't be cheap for them to do. Especially for customers like me in Europe as they have a much higher shipping cost and send FedEx Priority. I'll be an Ohmmu customer for life based on that alone.
 
The difference in weight isn't noticeable in acceleration, cornering, efficiency, etc. even with careful measurement. Not to say it does nothing, just that it would have to be one of a long list of other expensive weight reductions.

They haven't been in use in Model 3 long enough to really tell if they last longer and meet all claims.

Could be a downgrade in cold weather as unlike an ICE vehicle, there's nothing nearby to warm it much.

IIRC they've sold about 60 of these ones specifically.

I'm tempted to whip out my dynamics textbooks and school everyone here
Camalaio is correct


don't do it for "performance" do it for other reasons
 
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So you would have to contact Ohmnu for the full answer as to what’s programmed into their BMS. But I run lithium iron phosphate in my boat and it’s generally recommended that they not be charged at less than 32 degrees F, however any power being drawn out of the battery will warm it. Usage below 32* is fine but the capacity may be less than the battery aH. It’s only charging that’s an issue but some marine applications guys just turn a light on or something to draw power then charge or charge right after usage when it’s warm, or if kept in a garage the battery itself is usually warmer than the ambient air due to enclosure and also from the actual battery enclosure/case.
 
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Sorry if I’m late to the thread, but does it seem the 18-24 month battery life is more common in hot climates? I was wanting to avoid any major issue on a spring road-trip by preemptively replacing it as I approach the 2 yr mark, but I’m not in a hot climate and car is mainly garaged when not in motion. Thoughts?
 
Sorry if I’m late to the thread, but does it seem the 18-24 month battery life is more common in hot climates? I was wanting to avoid any major issue on a spring road-trip by preemptively replacing it as I approach the 2 yr mark, but I’m not in a hot climate and car is mainly garaged when not in motion. Thoughts?
As cheap as a new battery is, if I was at the two year mark and planning a road trip I would have no second thoughts and replace it with another OEM battery.
 
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Did you follow up and see if the depletion test was conducted and what the stats/results were?
I asked them 3 times if they were OK with performing the depletion test. I then provided my email after they told me that was the preferred way to receive the results, and I provided my Tele # in case of any questions or problems.

Then ... crickets.

If you think you can do better -- by all means, have at it.
 
i have the same battery as the mpp and had a custom 3d printed base to use the factory mount and its been great so far had over a year i believe and over 30,000km in that time never a issue live in southwestern ontario its been in all year summer over 100f and below 0f in the winter no problem at all, as mpp said earthx is well known for indy, plane and others works great imo everything mpp i have has been great quality as well as the service.
 
Has anyone with a constant drain tried either the MPP or Ohmnu. I have a radar detector installed that stays on all the time cuz of sentry.
Why would the battery type here matter?
If you have sentry on, the DC-DC converter is on and the battery isn't even in use.

That said, Ohmmu isn't shipping right now as a recent firmware update to the car started throwing codes and they are having to revise their design.
 
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