999zip999 said:What lifepo4 cell ? No need to go above 52v or 3.5 v per cell. The cell and capacity or ah with determine at what amps you can charge this battery at. Along with the limitations of the BMS if you're running one.
Yeah, that's an unusual configuration. 16s is the common "48V" standard. Can you rebuild the pack to 16s 7-8p? That would open up a lot of safe, cheap options.Skirmish said:k2 26650 lifepo4 in 15s 8p.
I think I've been searching for the wrong thing, I haven't had a lot of luck finding a charger at around ~54v.
999zip999 said:Yes 16s is common and 15s is something you have do on your own. Why why 15s ?
It's less than 7% loss of Wh to reconfigure to 7p16s. Or just buy 8 bare cells for 8p16s for a 7% Wh gain.Skirmish said:The cells I bought came only in bulk, in a number divisible by 15 not 16.
Is there an advantage to running 16s vs 15s if the controller + motor + charger work fine with either configuration and the power available with 15s is adequate?fatty said:It's less than 7% loss of Wh to reconfigure to 7p16s. Or just buy 8 bare cells for 8p16s for a 7% Wh gain.
I would design the pack around the charge and discharge profiles, not an arbitrary number of cells.
Higher voltage at same power = lower current = more efficientSkirmish said:Is there an advantage to running 16s vs 15s if the controller + motor + charger work fine with either configuration and the power available with 15s is adequate?
Skirmish said:Could I use the Mean Well HLG-320H-54A for 15s and 16s?
It lists the constant current region from 27-54v and an adjustable output range of 49-58v https://www.meanwell-web.com/content/files/pdfs/productPdfs/MW/HLG-320H/HLG-320H-spec.pdf
Skirmish said:Will the PSU overcharge the cells if it's configured to output 54v for 15s?
I was planning to add a cheap Volts / Amps display from aliexpress, eg. https://www.aliexpress.com/item/32788030454.html and checking for it to hit 54v / low current and then turning the PSU off.
If I can stop charging automatically that would be really handy though. I'm not familiar with HVC, I had a bit of a poke around but couldn't find an example. Do you have a link to somewhere I could find a suitable one or some more information?
Thanks in advance!
999zip999 said:Can't you buy a few more cells
Skirmish said:999zip999 said:Can't you buy a few more cells
Good idea, I'll shoot them a message and see what they say. Just looking at their web shop shipping is going to roughly double the cost. If I absolutely have to do that I guess that's what I'll have to do
I'll be using a BMS.
Skirmish said:Yeah, definitely. I'm hoping the cell retailer can do a smaller order, otherwise it's going to get a bit expensive. Fingers crossed.
Would the extended life be from a shallower DoD?
unknown, but generally the lower DoD the better. how much you gain is depending on your specific use case.
I was wondering how the HLG-xxxH-54A would behave with it's max Vo set to below 58v: would that run CC up to the Vo set point? Would that affect the life of the cells?
The V setpoint is maximum it should allow. CC is just a label for the first part of the cycle, before the setpoint is reached, aka Bulk.Skirmish said:Would the extended life be from a shallower DoD?
I was wondering how the HLG-xxxH-54A would behave with it's max Vo set to below 58v: would that run CC up to the Vo set point? Would that affect the life of the cells?