12V Battery Swap/Upgrade

[Btr_ftw]

Hey guys

I don't have the luxury of having a fancy dancy vehicle warranty like most of you here, but the 12V Batteries in my cars are long dead. Have any of you here upgraded or replaced the 12V battery in the Model S with a different/better brand? I know the 12v batteries die on average of once a week, so I'd like to only have to replace it once mostly due to cost and difficulty.

I plan on connecting it to a tender as well just in case.

 

[Edmond]

Yes I have no confidence in the brand that Tesla chose. At least they've moved to deep cycle.

I gather that a new Tesla battery is $400, but when mine goes I'm out for alternatives, and I've found several deep cycles which are the same size or larger and vastly cheaper, just doing a search. Or, depending on my circumstances at the time of failure I may spring for Stark Power | Lithium Starter Batteries & Energy Storage Batteries

 

[FlatSix911]

Yes I have no confidence in the brand that Tesla chose. At least they've moved to deep cycle. I gather that a new Tesla battery is $400, but when mine goes I'm out for alternatives, and I've found several deep cycles which are the same size or larger and vastly cheaper, just doing a search. Or, depending on my circumstances at the time of failure I may spring for Stark Power | Lithium Starter Batteries & Energy Storage Batteries

Li-ion looks like a good idea ... it will be my next replacement 12V.

 

[Edmond]

I think 30Ah is inadequate. 50Ah is the same physical size. (although it is $200 more, it's worth it)

Hmm..

It is best for the "UltraEnergy" battery not to be trickle charged but to use advance chargers that turns OFF charging current when the battery is completely charged at 14.6V. StarkPower sells "Smart" chargers for lithium batteries. Using lead acid chargers that charges up to 16V, along with leaving them ON, will damage the Lithium battery over extended time.

Marketing/scare hype. Almost all cars charge at 14.5v.

StarkPower’s “UltraEnergy” are to be used for energy storage applications and NOT for engine starting applications.

Common for deep cycle, so it is fine for our application, but charging is a question. Either it doesn't have a BMS (unlikely), or they're trying to scare us into their charger.

Their 12V LiFePO Charger 10A is very basic, constant current and threshhold cutoff. Not to mention, inappropriate for us as it has AC input. I'm going to say the Tesla charger is fine.

 

[Btr_ftw]

Interestingly enough, when switching battery brands (from C&D to Exide) you must reflash the vehicle according to the Tesla TSB

The TSB Instructs you to go to...

Views - Vehicle Information - Vehicle Configuration Update

Change 12V Battery type to C&D


There may be something else we are missing here if the car "requires" a reflash just to change battery brands...

 

[qwk]

Interestingly enough, when switching battery brands (from C&D to Exide) you must reflash the vehicle according to the Tesla TSB

The TSB Instructs you to go to...

Views - Vehicle Information - Vehicle Configuration Update

Change 12V Battery type to C&D


There may be something else we are missing here if the car "requires" a reflash just to change battery brands...

 

[Fusion]

I think this car just needs at least a deep cycle battery. The Rav4 EV had the same problems with the 12v battery. Probably due to having the same internals as the Model S.

Toyota Rav4 EV Forum • View topic - 12-volt battery replacement