Secondary Battery question....homemade LiFePO4

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nateh

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I recently build a LiFePO4 battery for a café racer motorcycle project as my primary power source that worked out really well. I'm looking to add a secondary battery to my rig for accessories, etc. I wanted the community's advice/opinion on this as I've never ran a secondary battery before and wasn't confident what kind of parameters I should be concerned with. Here's the plan:

8x26650 LiFePO4 cells (These ones)
Each cell = 2500mAh, 3.3V, 50A max continuous discharge. 120A max pulse discharge (10s)
Configuration: 4s2P which would give me: 10Ah(?), 13.2V, 200A max continuous discharge, 480A max pulse discharge (10sec)...I believe

Rig and planned uses:
2005 Land Rover LR3
No fridge (yet)
LED camp lights (exterior)
LED light strip(s) (interior)
Basic cell phone charging
OEM incandescent interior lighting (may convert to LED one day)
I have a 12,000lb winch that draws up to 350A at max load but may not try to use that off of this battery unless absolutely necessary
Vehicle sound system

Would you all expect this to be sufficient for some of these basic uses? Let's say I add a fridge or something like that, would it be able to handle that fine? I'm considering a small solar charger down the road that I think should be able to assist with charging fairly well since these types of batteries seem to charge up quite easily. They're also incredibly small for the power they have. My motorcycle battery all soldered up and shrink wrapped is about the size of large sandwich. LiFePO4 is also much more stable and you can utilize up to 80% of its capacity without harming the battery, unlike LA. If my calculations are correct I would theoretically have the capacity use my winch at peak 350A load for around 1:20, assuming 80% discharge was safe. So in a pinch it would work, without my main battery or the vehicle running at all.

Anyways, I'm open to thoughts/critiques/tips!
 

smritte

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I get mine here Battery Hookup
They also sell diffrent sizes with a BMS included.

Personally, I prefer simple on my rig. Dual AGMs and i'm good for anything. I could run lithium's but I don't see the need other than the cool factor. I run a solar panel and that keeps my batteries topped, either will (and have) power my winch.
 

M Rose

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Until battery heaters come down in price home
Brewed LiFePO4 batteries aren’t the way to go…
 

nateh

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Pocatello, ID
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One reason for this is I already have 8 of these sitting in my garage and I'd like to make use of them
 

leeloo

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Operating temperature is not the same as charging temperature .For many it means they can be discharged at -x .
Unless they have a built in heater inside, if they are indeed LIFEPO4, they will be destroyed if you attempt to charge them at negative temperatures.