Cooling for diy LFP pack?

[Willfulone]

I am designing a system for my sailboat. somewhat concerned about heat being an issue at times. Wondering if anyone has made a pack with cooling? Maybe a pelteir cooler or something? Fridge compressor? Please chime in with any ideas! Thanks!

 

[Supervstech]

I mean… on a boat, there is usually a fairly large cooling source nearby… no? Seems simpler to plumb in a small pump to use the water…

 

[brum]

Water cooling, but only if needed. I doubt that the boat doesn't have suitable compartments for the batties that can keep acceptable temperatures.

 

[svsagres]

At least in my case, the battery is next to the hull, so that will moderate things pretty well, passively.

 

[Msg43]

As a commenter recently said in a great YT video on this subject, ambient heat has a large impact on cycle life so there is an ROI in keeping the pack cool.

I am in the process of building a large pack for my all electric boat (1200Ah @ 108v using 144 EVE 302s). I have successfully used a Termodinámica 16k BTU water cooled hvac system on another boat which runs on DC power and is very efficient. I am planning to route a duct through the battery compartment to keep them cooled.

HVAC unit: https://termodinamicausa.com/products/24v-unit

 

[wholybee]

Active cooling like a pelteir cooler or Fridge compressor is going to use quite a bit of power. Water in the tropics is upwards of 85F, so that isn't much help either.

If this is a large battery for an electric propulsion systems, that opens up options as you have the power available to run some real cooling. But if it is just a moderate sized house bank charged by solar....

I have just accepted that I will had shortened life, but still expect my LFP to last many, many years. After more than 1 year I am less than 100 cycles, and I still test capacity at 110% of rating. So if I get 1000 cycles or 1500 cycles instead of 2000 cycles, that's still 10 or 15 years.

 

[Willfulone]

Active cooling like a pelteir cooler or Fridge compressor is going to use quite a bit of power. Water in the tropics is upwards of 85F, so that isn't much help either.

If this is a large battery for an electric propulsion systems, that opens up options as you have the power available to run some real cooling. But if it is just a moderate sized house bank charged by solar....

I have just accepted that I will had shortened life, but still expect my LFP to last many, many years. After more than 1 year I am less than 100 cycles, and I still test capacity at 110% of rating. So if I get 1000 cycles or 1500 cycles instead of 2000 cycles, that's still 10 or 15 years.

460Ah 12v house bank. I havent run across anything simple and low power draw.

 

[400bird]

You could get something like this, if you want to cool the battery compartment.

12V Compact Cooler - Compact, Light, Rugged Liquid Cooler for Local Cooling

12V Compact Cooler - Compact, Light, Rugged Liquid Cooler for Local Cooling, racing, driver cooling

www.rigidhvac.com

They also liquid chillers if you'd prefer that.

 

[willo]

Honestly? Get a FLIR cam for your phone/tablet and address the hot spots. This'll make a huge difference.

 

[chrisski]

Fridge compressor?

I think this is a genius idea.

I would have designed my 280 ah 16 cell build to fit in a small fridge.

I store my RV where internal temps will reach 110 f for up to six months. The batteries will be at 50% SOC, but still outside specs.

I had thought of AC in the pass through compartment, but that’s 500 watts continuous. I think a refrigerated box would be much better.

I’m finding my batteries put off very little heat charging or discharging at 75 amps for long periods of time.

 

[willo]

I think you're better off looking at passive cooling designs - that doesn't mean that they don't have a fan but you can build a cooling loop that circulates by virtue of the heat produced and the cooling of say, a radiator that's external. Compressor's add quite a bit of complication.