LiFePO DIY battery

[MonsTT]

Hey guys,
Has anyone ever replaced the battery on the XT600/TT600E to a LiFePO a123 26650 cells, how many cells were enough ?
I tried 8 cells (4s2p) and the starter would hardly budge, any ideas?
Tx

[xtrider]

I've been running an 8 cell Ballistic LiFe PO4 in my hi comp , no decompresser XT for 3.5 years now , spins it over easily whereas a standard battery wouldn't get past the first comp stroke . I had to make my own power cables using 4 or 6ga and heavy ends to allow the juice to flow , the oem cable were getting hot quickly .



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[MonsTT]

I'll try again after swapping the wires to a thicker gauge, perhaps too much energy is wasted on heat, after all it should've been enough with a discharge current of 240 A.
Thanks

[xtrider]

I'm pretty sure I used a 4ga wire for the positive cable and 6ga for the negative , been a few years since I did it . Possible they're both 4ga , but I know they were about 2ga heavier than stock plus the heavier copper ends . If your motor is stock then the lighter ga will work fine . The stock cable couldn't carry the juice good enough for how my motor required and it would turn over rather slow even with the new battery but once the new cables were one it spins over easily . The stock cables were likely getting bad as well , maybe new oem ones would have worked but with the amount of juice these new batteries can put out it's best to have better cables .

If your making your own battery and just using individual cells , makes sure you have them hooked correctly and with solid connections , just one poor connection will stop all the cells from sending full amps , same as with the cables.


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[MonsTT]

Hi Guys,
For the closer of the post and for the benefit of future projects:
The problem was indeed due to the poor connection between cells, although voltage checked ok, high current flow was prevented.
Initially I bought the battery housing on ebay, problem got fixed once I customized my own 0.4 mm (thickness) copper stripes to connect between the cells.
anyway, now the motor turns easily.

Cheers
MonsTT