Hi all,
I'm thinking of building a new, larger battery pack for my 36V "500W" BBS02 Yuba Mundo touring cargo bike.
My current plan is to buy a Crystalyte RB3 battery bag from Grin Tech (since I need to place an order with them anyway) and a bunch of Samsung INR18650-30Q cells from nkon.nl.
The grin tech site says the RB3 dimensions are 31cm x 18cm x 13cm, but I'm not sure if that's internal or external dimensions. I don't know how many cells I'll be able to fit into it, I'd really like to fit 10S10P or even 12P but that's probably too much. Anyone have recommendations for a bigger padded battery bag?
I also need a BMS. I like to overspec my components to extend their life, so I'd be looking for something rated for 40A continuous discharge, 12A continuous charge. I'd also like one that does real cell balancing. What's the current recommendation for reliable balancing BMS?
Once I have the cells soldered, I was thinking of using some of that huge heat-shrink tubing I've seen in other battery pack build images that goes around the whole cell group/pack. Where would I get some of that? The only heat-shrink tubing available here is the small regular tubing.
EDIT: Will probably use 18650 holders like these: https://www.aliexpress.com/item/High-Quality-100X-18650-Battery-Safety-Holder-Bracket-Spacer-Radiating-CLidless-Battery-Pack-Free-Shipping/32566942346.html but would still like to wrap the whole thing in heatshrink.
This would be an extra battery for looong camping trips out into the deserted parts of Iceland (I have a couple of 10S6P downtube batteries for my day-to-day). So I wouldn't mount it anywhere, I'd just throw the battery bag into my cargo bike panniers or on the Yuba rack when needed and plug it into my power wire through an Anderson extension cable.
EDIT: Oh yeah, I'd also prefer the BMS have temperature monitoring. Do they generally have one temperature probe channel per charge group? And do I just stuff a regular NTC/PTC thermistor between the charge group's cells?
Any other ideas or suggestions? Something stupid in my design, or things I could do better? I haven't ordered anything, so now is the time for changes.
I'm thinking of building a new, larger battery pack for my 36V "500W" BBS02 Yuba Mundo touring cargo bike.
My current plan is to buy a Crystalyte RB3 battery bag from Grin Tech (since I need to place an order with them anyway) and a bunch of Samsung INR18650-30Q cells from nkon.nl.
The grin tech site says the RB3 dimensions are 31cm x 18cm x 13cm, but I'm not sure if that's internal or external dimensions. I don't know how many cells I'll be able to fit into it, I'd really like to fit 10S10P or even 12P but that's probably too much. Anyone have recommendations for a bigger padded battery bag?
I also need a BMS. I like to overspec my components to extend their life, so I'd be looking for something rated for 40A continuous discharge, 12A continuous charge. I'd also like one that does real cell balancing. What's the current recommendation for reliable balancing BMS?
Once I have the cells soldered, I was thinking of using some of that huge heat-shrink tubing I've seen in other battery pack build images that goes around the whole cell group/pack. Where would I get some of that? The only heat-shrink tubing available here is the small regular tubing.
EDIT: Will probably use 18650 holders like these: https://www.aliexpress.com/item/High-Quality-100X-18650-Battery-Safety-Holder-Bracket-Spacer-Radiating-CLidless-Battery-Pack-Free-Shipping/32566942346.html but would still like to wrap the whole thing in heatshrink.
This would be an extra battery for looong camping trips out into the deserted parts of Iceland (I have a couple of 10S6P downtube batteries for my day-to-day). So I wouldn't mount it anywhere, I'd just throw the battery bag into my cargo bike panniers or on the Yuba rack when needed and plug it into my power wire through an Anderson extension cable.
EDIT: Oh yeah, I'd also prefer the BMS have temperature monitoring. Do they generally have one temperature probe channel per charge group? And do I just stuff a regular NTC/PTC thermistor between the charge group's cells?
Any other ideas or suggestions? Something stupid in my design, or things I could do better? I haven't ordered anything, so now is the time for changes.
