Building a lithium battery

[gregcope]

Jenny Woo - somone who Rays builds Cool stuff on youtube recommends (https://www.youtube.com/channel/UCEW1Dv7_YieagyEvxUpL10Q) has EVE 280K cells in the UK for $100 each!

No connection, never used her and no idea if these are grade A... buyer beware.

However interesting that lifePo4 cells seem to be dropping in price.

 

[Vickrohhk]

Regarding fuses, using the fuse connector as a bus bar between the batteries sounds like a solid plan, but having individual fuses on each battery could add an extra layer of protection.

 

[geem]

Regarding fuses, using the fuse connector as a bus bar between the batteries sounds like a solid plan, but having individual fuses on each battery could add an extra layer of protection.

How you fuse may depend on the size of the batteries. A single 12v 100Ah lifepo4 battery will not have the same AIC requirement as a pair of 280Ah 24v batteries. A single NH type fuse would be fine for the 12v 100Ah battery but each 280Ah 24v battery should be fused individually with an NH fuse. Additionally, each 280Ah 24v battery should have its own isolator.
The best arrangement for lifepo4 batteries is individual fusing and isolators and then common busbars for both +ve and -ve loads.

 

[gregcope]

The best arrangement for lifepo4 batteries is individual fusing and isolators and then common busbars for both +ve and -ve loads.

This is how mine are. Battery-> T class fuse->isolator->shared +ve bus bar.

They have identical lengths and resistance.

 

[Vickrohhk]

Regarding fuses, using the fuse connector as a bus bar between the batteries sounds like a solid plan, but having individual fuses on each battery could add an extra layer of protection.

As for your MPPTs, leaving them connected straight to the battery on the positive side shouldn't cause one battery to charge preferentially, especially if they're connected by heavy cables.
Have you ever considered trying a lipo battery pack for your setup? I've heard they can offer some great performance benefits, especially in terms of energy density and discharge rates.