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12v Battery - Using LiFePO4

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My choice for battery three years ago was the Bioenno BLF-1250AS, LiFePO4 (Lithium-Iron). Yeah expensive, but:
- Inherent thermal and chemical stablility, so no runaway like LiIon
- 50AH vs C&D's 30AH (yeah it's an inch deeper - had to make a new strap)
- Provides 2500 - 7000 cycles & a 10 year lifetime compared to 200 - 500 cycles & a 3 year lifetime for C&D.
- Holds above 12V for up to 90% of its capacity usage providing huge boosts in run-time compared to only 50% in lead acid.
- Use of phosphates avoids cobalt's awful environmental concerns.
- Bioenno's customer service can't be beat. Had a problem with my battery after a year and they replaced it, no pro-rate, no fuss.
 
Excellent! C&D is the the original Tesla AGM or similar battery they put in, or is it something else? I haven't seen that acronym before. Also I'm not sure what 12 V battery Tesla is putting in its latest vehicles as a standard. It seems to be sensible for them to switch to something like LiFePO4 or their own li-ion battery technology such as that used in the Model S / Y etc.
 
My 5 year old original Model S battery is still working just fine. I do expect that some day it will die but I think I'll just replace it with the same. I know that Li batteries are "better" but at twice the cost, I just don't think it's worth it. If the replacement Pb battery gives me another 5 years of service, I'll be happy.
 
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Excellent! C&D is the the original Tesla AGM or similar battery they put in, or is it something else? I haven't seen that acronym before. Also I'm not sure what 12 V battery Tesla is putting in its latest vehicles as a standard. It seems to be sensible for them to switch to something like LiFePO4 or their own li-ion battery technology such as that used in the Model S / Y etc.
C&D is the brand of the OEM Tesla 12v battery. Indeed it is AGM and deep-cycle.

Battery manufacturers often create front companies to name their products, out of fear of liability for lead contamination and other issues. If problems blow up they just bankrupt that front company.

Tesla is pretty much unparallelled in the capacity of their main pack cells, but LiIon always has the potential for thermal runaway. A while back Sony started having lots of fires in their LiIon batteries and it turned out that their manufacturing equipment was dropping metal shavings onto the band. Also LiIon is much more sensitive to cold than Pb batteries, although it is rated at twice the dis/charge cycles.

LiIron (LiFePO4) by its nature is extremely stable and is not subject to thermal runaway, even when crushed or punctured. And it lives for almost ten times as long as Pb battery. Those getting 5 years out of their Pb battery are crazy lucky, and they (should) know it. I bought a wrecked P85D that was 4 months old -- the 12v battery was smashed and I could see that it was already quite sulphated. True, LiIron is more sensitive to cold than Pb, but if you look at the specs it's not a problem in most areas of the world.

If you buy a LiIron battery check the dimensions and get the highest capacity you can with about the same dimensions as the Tesla OEM battery. (which is 33AH) If memory serves this is about a 60AH LiIron model. Get two mating adapter cables, and their 10amp charger just in case.
 
My choice for battery three years ago was the Bioenno BLF-1250AS, LiFePO4 (Lithium-Iron). Yeah expensive, but:
- Inherent thermal and chemical stablility, so no runaway like LiIon
- 50AH vs C&D's 30AH (yeah it's an inch deeper - had to make a new strap)
- Provides 2500 - 7000 cycles & a 10 year lifetime compared to 200 - 500 cycles & a 3 year lifetime for C&D.
- Holds above 12V for up to 90% of its capacity usage providing huge boosts in run-time compared to only 50% in lead acid.
- Use of phosphates avoids cobalt's awful environmental concerns.
- Bioenno's customer service can't be beat. Had a problem with my battery after a year and they replaced it, no pro-rate, no fuss.
I'm really confused as to why you're touting this battery as a replacement for the AGM?
1. The cost is almost astronomical
2. It cannot be charged using the electrical circuit from the Tesla
3. You must purchase and use their proprietary charger regularly to charge the battery

Seems like a lot of work and money is involved and how do you figure out how often you have to charge the battery with their charger? Too much work and guessing involved for me.
 
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I'm really confused as to why you're touting this battery as a replacement for the AGM?
1. The cost is almost astronomical
2. It cannot be charged using the electrical circuit from the Tesla
3. You must purchase and use their proprietary charger regularly to charge the battery

Seems like a lot of work and money is involved and how do you figure out how often you have to charge the battery with their charger? Too much work and guessing involved for me.
Strangely, I've run my battery in my P85D for 3 years and no problem -- oh except for the early-gen one I first bought where the terminal started to turn because it came loose from the bonding. They immediately replaced it with a new-gen which has terminals on the short edge and extensive redesign resulting in it being 2/3 the size of the old one (and 3/4 the size of the C&D), yet still with 50% more capacity than the C&D and 10x the lifetime. Now; this replacement was with a year's use on the old battery, and they did it without any hassle. This is how I know about their customer service.

If you're familiar with arithmetic, and expect to replace your C&D every year or so, and do not like downtime, again (and again) the Bioenno costs out far better.

The DC-DC charges it just fine, in fact to a level which balances its cells. Yes you have to faff with the adapter cables at install, but I like that better because I mess with my car alot and the quick-connect is real nice. And some day it may get out of balance so I have the charger, which they provided for free due to my problem with the old battery.

To each, his own. I am just trying to help. This company is recommended.

Caveat: I am the only one known to have bought this battery, but then its technical merit is beyond reproach and that is something I can't resist. We all make our choices.
 
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Tesla is perhaps the most knowlegable producer of Li Ion batteries in the world. Imagine if they felt that Li Ion would be a better source of the 12V, they would install them.

They have the most to lose with the batteries limited life, as they are the ones responsible for replacing them at no cost during the warranty period.
 
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Why would you expect to replace the C&D every year when they apparently last many, many years? The physical size of the battery is of no consequence as long as it fits in the compartment the original was designed for. It's not like you can use that space for anything else. Why does Bioenno only offer a 2 year warranty? As far as I can tell, the only material difference is the weight savings.

The charger provided with the Bioenno is not a balancing charger. It charges through the discharge leads like any other battery charger. From the description, it sounds like the balancer is built into the battery.

OTOH, if I were in the market for a new battery, I might consider the Ohmmu for $419. Saves $50 and you get twice the warranty of the Bioenno. I have no stake in either company BTW. However, I find it odd that you have stooped to personal attacks against those who disagree with your choice or even question your motives for buying this battery. Not the best shill post.
 
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Tesla is perhaps the most knowlegable producer of Li Ion batteries in the world. Imagine if they felt that Li Ion would be a better source of the 12V, they would install them.

They have the most to lose with the batteries limited life, as they are the ones responsible for replacing them at no cost during the warranty period.

Except that nobody is talking about Lithium Ion. Totally different chemistry with 3 times the charge/discharge cycles than Lithium Ion and more importantly isn't damaged by charging to 100% like regular LiIon batteries are.

Why doesn't Tesla make this the standard battery? Cost. It costs more than the lead acid AGM. Plus they won't make as much charging you to replace it every year or two since it will probably last 7 years.

That said, it's still too much for my taste and it only takes me 5 minutes to replace my battery.

Update: Even I read the OP wrong. He actually said Lithium Iron but left off Phosphate and with the small font I thought it said Ion.
 
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Tesla has just switched the main pack to LiFePO4 in Red Chinese M3's.

Problem I've found now with this replacement LiFePO4 battery is its BMS is able to hold above 12v for most of its discharge cycle... so the car often misses charging it in time. It's a new problem. Great for holding a steady voltage, but intended for asynchronous charging like solar.
 
Tesla has just switched the main pack to LiFePO4 in Red Chinese M3's.

Problem I've found now with this replacement LiFePO4 battery is its BMS is able to hold above 12v for most of its discharge cycle... so the car often misses charging it in time. It's a new problem. Great for holding a steady voltage, but intended for asynchronous charging like solar.

Has that been confirmed? Source?
 
Tesla has just switched the main pack to LiFePO4 in Red Chinese M3's.

Problem I've found now with this replacement LiFePO4 battery is its BMS is able to hold above 12v for most of its discharge cycle... so the car often misses charging it in time. It's a new problem. Great for holding a steady voltage, but intended for asynchronous charging like solar.
What about the other colors of Chinese M3s?
 
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They don't make the 12v battery a Lithium Ion battery because it doesn't have any heating or cooling like the main pack does so it wouldn't last as long as a lead acid battery due to the temp fluctuation . What's the benefit of spending 2-3x as much vs the battery that comes in the car/sells? Replace is every 6 years instead of 4? Save 15 lbs? Doesn't seem worthwhile to me, especially if your car is under warranty.

BTW. here is a pic of one that Tesla just replaced in my car:
EWKYNna.jpg
 
Has that been confirmed? Source?
Tesla wins China approval to build Model 3 vehicles with LFP batteries: ministry

What about the other colors of Chinese M3s?
Ok you get your Funny rating.

But everyone forgets that this is still RED China, as in Communist, that we are talking about. The governing structure has never changed and it baffles me how rock-ribbed Republicans can now cheerfully overlook this little matter.

When the UK gave up Hong Kong, Red China began adopting some of their business mechanisms, at the same time that the Bush Administration enacted tax CREDITS to outsource work to China and India. Yes, tax CREDITS. This resulted in a massive jobs export, and the world's greatest technology transfer of knowledge which took us decades and $trillions to develop. FOR FREE! You're Welcome Red China.

The US has single-handedly pulled Red China out of poverty by exporting a large chunk of our economy and priceless knowledge to them. And now we will be having problems with Red China from now on.

It was the Mistake Of The Century, as slavery was of that era. Yet everyone's too stupid to see.
 
If you don't live in a snow area, it's probably not an issue.
My lithium batteries in my motorcycles are at least 5 years old each.
They work great except below 20°F and cranking power, something EVs don't have to worry about.

But the most important issue for those with cars under warranty, is that Li batteries are not deemed as acceptable replacements for AGM batteries.