80Ah ADD ON build

[shirley_hkg]

Oh Ok -
pretty sure i need to make cables to connect them - those connectors i dont think will fit - reach once i add the silicone sheet in between cells - there were tight just close enough with nothing in between - dont see it working out with them - too bad would have made it easier for me -

As you said , it's thin and soft . Use an office punch to make a elongated hole to accommodate the displacement .

[expresso]

Ok well i managed to loose the charge graphs again on this cell - the preset has a 4 hour CV - - it just stopped - i went to check - i seen it had close to 75ah returned i reset it and realized i never saved the graphs snapshot of them - so again i dont know for sure but its close to 75ah now - if thats the case its the same as my previous 60ah cells - that end up at 55ah usable down to 2.9v - i bet these will be very close to 75ah when i get around to testing the whole pack discharging.

they are correct if you discharge down to 2.5v - so they didnt lie that its 80ah Cell - we just wont be making use of it all - 75ah is close enough if thats what i end up with at the end of the day - better safe then sorry - i wont be testing it down to 2.5V - i did change the preset now - made it CV cutoff to 8 hours - so tomorrow the next Cell should start and finish with no issues hopefully i get those snap shots of the graphs in the end.

[expresso]

Oh Ok -
pretty sure i need to make cables to connect them - those connectors i dont think will fit - reach once i add the silicone sheet in between cells - there were tight just close enough with nothing in between - dont see it working out with them - too bad would have made it easier for me -

As you said , it's thin and soft . Use an office punch to make a elongated hole to accommodate the displacement .

i was thinking the same thing Shirley - its an idea i may try at least - i dont have a office puncher - i may have to just buy one now to try that - will check amazon for cheap one - or i can try a dremel i have first - so maybe being thin may work out after all - i can use double for sure - i have enough of them

[expresso]

https://smile.amazon.com/Single-Puncher ... heavy+duty

this may work - or this one ? https://smile.amazon.com/Bead-Buddy-Dap ... punch&th=1

if i doubled up on the connectors - do i have to do something to make them stay together in contact or just screw them down is enough to make good contact across the whole connector ? you know sometimes you put two items together and they dont sit flush touching all the way across - not sure if that matters - as long as they reach and get screwed down ?

[expresso]

https://smile.amazon.com/RMP-Stamping-B ... merReviews

making me search more now and i found these also - if i needed - i think i can get these and punch my holes myself - i just have to measure the length i need etc, i can even cut them shorter - now i know better and make my own connectors if it comes to that from now on -

if i did use them - i can just use them as they arrive ? raw copper blanks - they seem thicker than the ones i have -

[Burgerman]

Use what you have.

[Scooterman]

I don't know how "NEW!" these are, but 16 mounted vertically 2P8S gives 24v 100ah? There's no product number for them so it's hard to google for prices?

[Burgerman]

U forgot something...

[Scooterman]

U forgot something...

Did I?

3.2x8v=25.5v
2x50ah=100ah

Termainals?

[Scooterman]

Ah! only 24v.

NO not for me, that's just my altruistic nature coming out, thinking of you guys.

I'm going BIG and FAST with the scooter. 50V 100ah+ 300A roboteq single channel 20MPH!!!

[Scooterman]

Ah! only 24v.

NO not for me, that's just my altruistic nature coming out, thinking of you guys.

Re: the headways, I was actually thinking of my Salsa. The reason I mentioned them is because they NEW OUT? and because of the WD consensus that the stated ratings are more reliable and ‘real world’ than unbranded cells. Although I expect they’re more expensive. I thought 16 cells is more manageable than say 72.

[Burgerman]

I don't know how "NEW!" these are, but 16 mounted vertically 2P8S gives 24v 100ah? There's no product number for them so it's hard to google for prices?

What are "these" ?? No link.

[expresso]

Use what you have.

i will buy the hole puncher at least and make the ones i have a bit larger hole - i changed the preset again - put it back to 4hour CV cut off as it was before but i upped the charge rate to 25A - i should get 2 cells a day done this way and its fine - they are large Cells - 25A charge is not alot for 80ah

i was using the same preset i used for the single Cells 15ah headways and just upped the charge rate to 10A - and now to 25A to get them done.

[Scooterman]

What are "these" ?? No link.

Ooh silly me!

http://www.headway-cn.com/en/showproducts.php?id=1751

[Burgerman]

Those will work, but are only 2c max, so you really need 150Ah to get good lifespan. And good range. Will that fit?

[Burgerman]

Those will work, but are only 2c max, so you really need 150Ah to get good lifespan. And good range. Will that fit?

[Scooterman]

Those will work, but are only 2c max, so you really need 150Ah to get good lifespan. And good range. Will that fit?

These are the measurement of the Salsa's battery compartment. They are the max dimensions so best to deduct 1mm or 2mm for safety.

267mm width
351mm length
231mm high (to underside of plastic battery cover).

But as you say only 100Ah...

[Burgerman]

https://www.lifepo4-batteries.com/sale- ... f-car.html

Something like these would be better?

176Ah D54* W173* H200MM

So 2 off: 4 cells is 216 plus say 5 bits of insulation at 2mm thick = 226mm total, x 173 x 200 tall. Thats 40mm shorter than the MK, same height same width.

[Scooterman]

Something like these would be better?

Yes they would definitely, and as you say they will fit.

They're nice big meaty cells POWER!

[expresso]

IF i had to make a Full Chair Pack today - i would use those also - 8 Cells and enough Ah to make it the whole day with some leftover -

[Burgerman]

The only issue with those is that they are 2c cells. So you really do need 176Ah. But its about enough. They will take a long time to charge compared to say the 10C headway's. And also useless for an add on pack unless its big, and using a diode, or two... But should be OK for the Salsa. Thats all providing they have the dimensions correct. Seems too easy doesn't it!

Will leave a 40mm x 350 empty space! Need to find 8 small cells to fit there.
So 8x 12Ah headway's... Adds another 12Ah to the 176Ah, so now 188Ah! And I have some. Should give reasonable range.

[Scooterman]

Will leave a 40mm x 350 empty space! Need to find 8 small cells to fit there.
So 8x 12Ah headway's... Adds another 12Ah to the 176Ah, so now 188Ah! And I have some. Should give reasonable range.

16 of these https://www.lifepo4-batteries.com/sale- ... ships.html (or similar) in a 2P8S would fit in my scooter, and would give the option at a later date of rearranging as16S.

[Burgerman]

Will also fit the salsa I think. Just.

[Scooterman]

Will also fit the salsa I think. Just.

Yes they would, with a little bit spare for the insulation.

[expresso]

https://www.aliexpress.com/item/4pcs-Hi ... 2e0equa0uT

same size at 100ah Cell -

[Scooterman]

https://www.aliexpress.com/item/4pcs-High-power-system-4s-3-2v-100Ah-lifepo4-battery-cell-12V-14-6v-pack-for/32839723292.html?spm=a2g0s.8937460.0.0.1dd02e0equa0uT

same size at 100ah Cell -

Ooh they're good, I will bookmark that page

[expresso]

They look good - -

3rd Cell done and have the graphs this time - if some is wasted to heat during a charge - then i should get an extra 5ah or more when fully charged with a discharge down to 2.9v - its close enough to there specs - they say anywhere between 79ah Min - 82ah - again i am sure they are testing it down to 2.5V to get those figures -
they say dont go past 2V to avoid damage - in there figures 2.5V is a safe cut off for the cells - either way - i would follow the 2.9V cut off when i test them and also when in use hopefully this should get me the range i am shooting for and have a safe amount left over to avoid BMS cutting off power in the Chair.

[expresso]

https://www.aliexpress.com/item/4pcs-High-power-system-4s-3-2v-100Ah-lifepo4-battery-cell-12V-14-6v-pack-for/32839723292.html?spm=a2g0s.8937460.0.0.1dd02e0equa0uT

same size at 100ah Cell -

Ooh they're good, I will bookmark that page

they look good - thats all i can say about them - just like my cells - actually those look even nicer - cleaner brand newer looking - mines are all generics i am sure - they call it GTK Brand - means nothing to me - could be worse than a AA Cell for all i know -

[expresso]

looks as if they may just give me close to 80ah even at 2.9v - if i am lucky

[ex-Gooserider]

IMHO it is cheap enough these days that everyone should own a basic 6" digital caliper - Amazon has promotions for under $5, regular in the US$10-20 range - digital is easy to read, and gives you both inch and metric (some even give fractional inch) and lets you measure to about 0.001" or 0.01mm with reasonable accuracy - good enough for all but the fussiest of stuff (if you are doing stuff that needs better, you will know it...)

These aren't necessarily be the top quality NIST traceable, etc. but will be close enough for any sort of every-day work... I own a fancy Starrett caliper, but almost never use it, as my cheapo e-bay digital does almost as good and I don't need to worry as much about dropping it or otherwise destroying it...

If you can measure the thickness and width of those copper connector strips, it is a simple math problem to find the cross section area, and then you can compare it to any decent wire gage chart to see what size has a comparable cross section... However I'd be willing to bet they are at least as good as AWG 10, probably better - no real need to double up...

However you do need to make sure that any fasteners you use are able to snug down tight, with NO movement of the hardware under them - if there is slop you WILL have connection problems, and they will be intermittent and difficult to find... So use the shorter screws / enough washers to make a snug fit...

ex-Gooserider