Cell recommendations - based on current UK/EU availability

Andy_L

100 µW
Joined
Apr 15, 2016
Messages
9
Apologies for another recommendations thread but am looking for help given the current state of the market.

I am looking to build 2 packs into custom shapes to fit 2 bikes I am currently converting using TSDZ2's. My requirements are:

Motor: 48V, 750W TSDZ2 running OSF with SW102 and no throttle, temp mod

Battery: Aiming for 52V 14S4P for myself and possibly 52V 14S3P for my wife (but may also opt for the same 4P).

Use: Mainly cycle path and gentle off-road, we will be only running in pedal assist, no throttle fitted and not interested in long runs at top power. My use will be heavier than my wifes as hence opting for a bigger 4P pack as i will also be pulling the dog trailer but the intention is to help us get out more together and let me tackle hills which currently are very hard work with the trailer. Ultimate speed etc is not an issue, just making rides more comfortable and so we can cover further distance. This wont be my main MTB as I have my big FS bike for proper rides by myself or with friends, I will be interested to see how far i can push this off-road but this is not my main intention.

Current: I believe the controller is limited to 18A but I would be happy to limit that to 15a in the software if needed as that is still 750W at 52V or maybe even lower (10A) as we will still be pedaling and I am likely to be fitting 34T or 36T chainrings to reduce current load as top speed is not an issue.

Charging: I am intending to be quite strict on reducing overcharging and abuse, if that is a smart BMS or using a smart charger I am not sure yet.

i would like to maximise the available Wh if possible for the size and weight but the biggest problem I am having at the moment is cell availability. Ideally I would go LH MJ1 but just no stock, I am not limited to 18650 format so would consider others. UK sources ideal thanks to Brexit but importing just fine as long as a reputable supplier.

thanks!
 
Bigger cells = less work, so 21700s seem to be the obvious cylindrical choice if you're not tied to 18650s

Fogstar Wholesale is UK and recommended
They have Samsung 50E OOS, but cheap if you can wait

Their non-wholesale site lists Molicel M50A, so you might email to see about wholesale

Or LiPo...
 
thanks fatty, I will take a look at those now and look at the packaging in my planned "enclosure" and space.

i did just see NKON has refurbished MJ1's coming back in stock for 3.10 euro + import/vat etc but unsure about cells that have been dismantled in case they were bad or got mechanically damaged when the nickel removed.
 
any thoughts on these:: https://eu.nkon.nl/lg-inr21700-m50-4850mah-7-3a-no.html?gclid=CjwKCAjwnPOEBhA0EiwA609ReeAGdJvzqnoDzzyOUFtOM_AxuLNXxckuemydoixp3KYLIaeD9CfagBoCU_gQAvD_BwE

low discharge but at 3P and 15A I would be running each cell at around 2/3rds it's max. No heatshrink doesnt concern me, better cooling and less weight, just got to be a bit more careful.
 
Andy_L said:
No heatshrink doesnt concern me, better cooling and less weight, just got to be a bit more careful.
It should concern you; your cells won't be warming up so cooling is irrelevant, and weight for a small number of cells is insignificant. They need to be wrapped for safety.
 
yes you are right, I am used to seeing cells without insulation but for an application I cannot discuss and my job was to protect the rest of the vehicle against thermal runaway of a lot of cells (which I did) but it would not take much to have an accident when putting this pack together, especially without all the dedicated cell holders.
 
Back
Top