24v pack, is it 7s or 8s?

[rg12]

Hey Guys,

I never messed with a 24v pack and am replacing the cells.
The cells were those silver packets ones and it had 16 of them (two paralleled in each channel) so it's an 8s.
The problem is, I figured that it's a LifePo4 pack (googled it and those silver packets, the lipo looking cells can also be lifePo4)
since it's 8s because it sums up to 33.6v topped if it was LiIon which is too much for 24v nominal voltage at all.
So I said no problemo, I will rebuild it with a different BMS for LiIon and put in brand new LiIon cells and make it a 7s to be a 29.4v topped.
The guy calls me and asks about the charger, if it will fit the new pack which I totally forgot about the charger thing so I asked him to send me a photo of the back of the charger, and guess what? the charger says LiIon 29.4v
Question is, does a full charge voltage of 8s LifePo4 pack equals to 29.4v which is exactly the max voltage for a 7s LiIon?

 

[rg12]

I have a new BMS for it (for LiIon) so will start working on it.
Thanks alot

 

[dogman dan]

I'm confused,, maybe reading this too early.

You are building a brand new li ion pack? Then it will need a charger to out put 7 times 4.2v.

It sounded a bit like you were going to replace some of the lifepo4 in the pack with li ion. don't do that.

 

[rg12]

I'm confused,, maybe reading this too early.

You are building a brand new li ion pack? Then it will need a charger to out put 7 times 4.2v.

It sounded a bit like you were going to replace some of the lifepo4 in the pack with li ion. don't do that.

It's all good now, I am replacing all the cells and the BMS inside the retractable battery case.

 

[cycleops612]

I'm confused,, maybe reading this too early.

You are building a brand new li ion pack? Then it will need a charger to out put 7 times 4.2v.

It sounded a bit like you were going to replace some of the lifepo4 in the pack with li ion. don't do that.

It's all good now, I am replacing all the cells and the BMS inside the retractable battery case.

are you rebuilding a silverfish battery housing using LFP? I am sure many would be interested in your build. specific cells used etc.

a lot of bikes are built for them and they mostly came with crap cells.

if so, can you give any idea what the maximum watt hours of pouch LFP cells that would fit in the housing would be? ie, could u e.g. have opted for a 20ah 24v pak?