Lithium batteries

[Thor 18]

Tried searching and couldn’t find any answers from the last 6-7 years.  Anyone using a lithium iron phosphate (LiFePO4) battery in their car?
 Optima yellow top died yet again, and on the surface it seems like a good solution for an occasional use car.  Significantly lighter, less drain just sitting still, etc.  there seem to be a lot of options for motorcycle or boat starting batteries, with only a couple for cars.  Seems like if I can actually get 5-6 years out of them it’s well worth the cost. 

[Exidous]

I'm using an Antigravity. ATX-HD-30 I think it's the version. You have to limit voltage to 14.4. The non restart version still has a safety cutoff so you don't damage the battery by deep cycling. Rest voltage charged is about 13.2v and it turns my 440 12:1 LS7 over rapidly.

[jwvand02]

I would also recommend Antigravity batteries. I'm not running one myself but know several people who are, and plan to move over to one when my current battery dies.

[Cobranut]

I've been considering using a small battery for my race car, either lithium or AGM, in parallel with an ultracapacitor bank.
Anyone tried this type of setup?

[Thor 18]

Exidous, Do you have a separate voltage limiter for it to run off the alternator?   How long have you had yours? 

Thanks. 

[Exidous]

My alternator is controlled by my ECU. I can set the voltage how I want. It's been about 3 years now. Not a lot of cycles on it though.

[kinger]

I've been considering using a small battery for my race car, either lithium or AGM, in parallel with an ultracapacitor bank.
Anyone tried this type of setup?

Yes I use this in my snowmobile.  Replaced a massive 22lb battery with 2.6lbs.  1.6 for the lithium battery and 1lb for the Ultra Cap.  Obviously cold is the problem but the ultra cap is amazing.  Without it the battery (Even a larger one) can't start the sled without "Warming it" for many minutes.  Even then the voltage drops out while cranking.  The Ultra cap, whirls over at 13V with no issue in any temp. 

[Cobranut]

I've been considering using a small battery for my race car, either lithium or AGM, in parallel with an ultracapacitor bank.
Anyone tried this type of setup?

Yes I use this in my snowmobile.  Replaced a massive 22lb battery with 2.6lbs.  1.6 for the lithium battery and 1lb for the Ultra Cap.  Obviously cold is the problem but the ultra cap is amazing.  Without it the battery (Even a larger one) can't start the sled without "Warming it" for many minutes.  Even then the voltage drops out while cranking.  The Ultra cap, whirls over at 13V with no issue in any temp.

That's awesome to hear.
Did you buy an assembled capacitor bank, or build it yourself?

[Thor 18]

Ended up buying an Ionic LiFePo4 starting battery.  Listed as for a boat or UTV, but only $250 for a 30 amp hour battery, vice $5-600 for the automotive ones.  Comes with battery monitor and restart capability if it drains.  Also has Bluetooth so you can monitor battery on your phone.  9 lbs vice 45, and fits in the rear bin much more easily. 
Starts the engine much more quickly than the optima.  Started 4 times in quick succession, ran the blower on max and headlights on with the engine off, and then drove for about 20 minutes to check charge rate and cutoff (took 7 minutes to get to full after being at 92 from the starts/fan).  So far I’m impressed.  I’ll update if it goes Samsung Note 7 on me. 

[Cobranut]

Ended up buying an Ionic LiFePo4 starting battery.  Listed as for a boat or UTV, but only $250 for a 30 amp hour battery, vice $5-600 for the automotive ones.  Comes with battery monitor and restart capability if it drains.  Also has Bluetooth so you can monitor battery on your phone.  9 lbs vice 45, and fits in the rear bin much more easily. 
Starts the engine much more quickly than the optima.  Started 4 times in quick succession, ran the blower on max and headlights on with the engine off, and then drove for about 20 minutes to check charge rate and cutoff (took 7 minutes to get to full after being at 92 from the starts/fan).  So far I’m impressed.  I’ll update if it goes Samsung Note 7 on me.

That looks like a perfect solution for my race car.
Thanks.

[MPbdy]

I’ve been using Shorai lithium batteries since we built my car. I’ve had to replace it once or twice but they weigh 5 pounds and last a good 3-4 years. Just don’t let them go flat that’s why I had to replace mine.

There are better versions available now with built in BMS to balance the cells I bet they’re way more resilient.

[kinger]

I've been considering using a small battery for my race car, either lithium or AGM, in parallel with an ultracapacitor bank.
Anyone tried this type of setup?

Yes I use this in my snowmobile.  Replaced a massive 22lb battery with 2.6lbs.  1.6 for the lithium battery and 1lb for the Ultra Cap.  Obviously cold is the problem but the ultra cap is amazing.  Without it the battery (Even a larger one) can't start the sled without "Warming it" for many minutes.  Even then the voltage drops out while cranking.  The Ultra cap, whirls over at 13V with no issue in any temp.

That's awesome to hear.
Did you buy an assembled capacitor bank, or build it yourself?

I bought it assembled with a 3D printed case from a eBay private seller, really just a guy assembling them.  Saved me a lot of time and the case he made is actually pretty good quality. 

[Thor 18]

I’ve been using Shorai lithium batteries since we built my car. I’ve had to replace it once or twice but they weigh 5 pounds and last a good 3-4 years. Just don’t let them go flat that’s why I had to replace mine.

There are better versions available now with built in BMS to balance the cells I bet they’re way more resilient.

I was only getting 2-3 years from the optimas, so that’s good news.  This one is supposed to cut off if the charge hits 25%, so hopefully that gives an extra level of protection. 

[Exidous]

The pulse current on that battery seems really good but for only 3sec. Continuous being 50A is a little bit worrisome.

[Thor 18]

The pulse current on that battery seems really good but for only 3sec. Continuous being 50A is a little bit worrisome.

I’ll see how it holds up.  Running fans/headlights/radio I was seeing 35 amps with the motor off.  Seems to charge at about 15-30 amps as well.  I don’t plan on using a whole lot of current with the car off at any point, so it seemed like less of an issue to me.