hi All Battery Cell Layout question

[billym1967]

hi all i'll do my best to ask this question.

i'm going to build a 50 cell battery 10s5p ive got a 52 cell housing. i found the layout, added a crap picture plan ive done.

now i no on each set of 5 i have to connect the 5 live and 5 neutrals, that's not a bother.

but once ive done that and have 10 sets of 5 connected. so when i connect each live to neutral as in my bottom pic. if i connect 1 to 2 then do i insulate to make sure that the connection only touches 1 and 2 and none inbeteen. hope ive explained and asked right.

also thats the cell pattern i found and it looks to me as it could be done more easerly. though not without some connections crossing over each other.

thanks in advance

 

[Deleted member 4366]

This is the pattern, but you should use cardboard washers on the positive ends to stop the strips wearing through the plastic heatshrink, which will cause a fire:

 

[billym1967]

thanks for the picture, sorry i forgot to add the layout i have

 

[Nealh]

No pic Billy.
On each cell positive use a paper/card gasket to bridge against any shorting when attaching bus bars.

 

[billym1967]

brill, thats what i though, can i use that organe tape stuff with the funny name lol

 

[billym1967]

also do you think this layout will be better than the one ive found

 

[billym1967]

i hope this makes some sense, do it seem correct for the + to - connections, or will i need all five connecting. i only ask as some ive looked at all 5 + and - in each rove are connected and in others theres only 2 connections between iach 5 row. if that makes sense.

 

[wheeliepete]

It's best to connect as many together as you can to spread the load over all 5 cells. If you only make 2, the cells you have the connection on will be under more strain.

 

[Nealh]

brill, thats what i though, can i use that organe tape stuff with the funny name lol

Kapton tape you could use but tricky to get to stick really as little in the way of surface area to stick to.
Better to use these proper ones

https://www.ebay.co.uk/itm/200x-18650-Battery-Insulator-Insulation-Insulated-Ring-Adhesive-Cardboard-Paper/263153191860?epid=2240727250&hash=item3d45270bb4:g:2roAAOSwKVFZlrOW

UK sellers cash in so cheaper to get direct from HK/China, some UK sellers charge £2 for 10 or 30 buy direct and get 200 or 400 for less. Nkon sell peripherals but only worth it if you are buying cells as well. As I have found they are useful for other smaller battery projects as well.

 

[Nealh]

i hope this makes some sense, do it seem correct for the + to - connections, or will i need all five connecting. i only ask as some ive looked at all 5 + and - in each rove are connected and in others theres only 2 connections between iach 5 row. if that makes sense.

Example of a DASKIT battery used on Oxydrive kits.

 

[billym1967]

Kapton tape you could use but tricky to get to stick really as little in the way of surface area to stick to.
Better to use these proper ones

https://www.ebay.co.uk/itm/200x-18650-Battery-Insulator-Insulation-Insulated-Ring-Adhesive-Cardboard-Paper/263153191860?epid=2240727250&hash=item3d45270bb4:g:2roAAOSwKVFZlrOW

UK sellers cash in so cheaper to get direct from HK/China, some UK sellers charge £2 for 10 or 30 buy direct and get 200 or 400 for less. Nkon sell peripherals but only worth it if you are buying cells as well. As I have found they are useful for other smaller battery projects as well.

ive ordered some, ive just ordered some, will make things a lot easier battery's from Nkon. thanks for the help. i'm just waiting for all the bits and can give it a go.

 

[billym1967]

so i got my cells today from NKON. Sony US18650NC1 2900mAh - 10A

first question there reading about 3.53 does that sound right.
problem is 2 are reading under 3.5 and 1 under 3.4 so doesnt sound good.
even worse 3 have been used, to with solder damage are ok but the 3rd is no good hardly any reading at all
so not a good start.

 

[wheeliepete]

Not dealt with NKON, but I think they have a pretty good rep. Prop. worth e-mailing them with a photo of the used cells to see what they have to say. Ideally you want all the cells at the same voltage before assembling your pack, within 0.01v. You will need a single cell charger or something like an imax B6 to do this.

 

[billym1967]

i have emailed them, but i wonder as well about the 3.53 as ones i do 10s5p does that mean the battery will only be 35.3v or is it because 3.53 is unchanged.

 

[wheeliepete]

New cells usually have a voltage of around 3.5/6v, as it a safe voltage for storage. Once charged the cells should show 4.2v.

 

[billym1967]

yes just read up lol. NKON are sending replacements out for the used ones and poor ones. so ive planed my layout. and if i cut the last to cell holder out i can squeeze the bms board in.

 

[billym1967]

so change of plan to a 10s4p. ive been messing and added some picture. any advise on does it look right would be great.

the bit i have concern with is the last picture and last 16 cells. do i need to put any battery insulators in

big thanks

 

[wheeliepete]

Don't be in a rush to build your battery pack. It's not a job you want to redo. Yes, you need to fit insulators to the + end of the cells. Be VERY careful placing unwelded strips on your battery like you have. It does not matter so much at the moment, but when you have one side of the battery connections done, it is very easy to short out the cells and red hot nickel strip is really hard to pick up and leaves nasty burn makes in your clothes and carpet. Ask me how I know.

 

[billym1967]

so this is whats getting me confused. so ive looked at a you tube vid of the same project as mine been built. and no mention of insulators being fitted, but ive just had a closer look and they look like there on

but ive also been reading this

http://www.ebikeschool.com/how-to-build-a-diy-electric-bicycle-lithium-battery-from-18650-cells/

and again no mention of insulators, so im guessing before a put the battery's in the holder, i fit the insulators like in thses pics

 

[wheeliepete]

Yes, fit them before you put the cells in the holder. You don't have to use them, your battery pack will work fine without, but they just provide added safety, which is no bad thing.