I am also using 150mm wheels pneummies with a 16T pulley on the motor and 60T on the wheel.
How do I pick my cells and the number in series and parallel? With the ESK8 calculator I can see that a 10S battery will be sufficient from a speed perspective and from what I’ve read in this forum, 10S4P seems pretty standard, but what does that equate to in terms of range?
Going from there, how do i pick the right cells? Ive seen that molicel p42As are quite popular as well as Samsung 30Q but there are so many to chose from. What mAh capacity range is best? What continuous discharge current? Does instantaneous discharge current matter? What other parameters to consider? Etc.
Am i right in thinking that the difference between a Smart BMS and a Daly BMS is that the smart one can work with an app to give you a profile of the batteries performance, whereas the Daly BMS balances cells but you can’t view them - which comes in handy when something with the board /battery goes wrong in that with the Smart one you can diagnose the issue (although if something is wrong there’s not much you can do anyway save taking apart the whole battery - which if your not a builder then doesnt really matter)…is that right?
(the battery im having made is a 12s2p p42a/40t in case that helps me determine which BMS to go for).
cheers mate. When you say you can catch a potential issue, I guess this would be like a safety measure - like say your board is performing poorly and you check the Smart BMS and discover one cell is dead, you would then stop using that battery because it could cause an accident or a fire? - Just trying to think of a real world situation
Yeah, you can see if the battery is going out of balance which could point to a whole host of things. Dead cell or dodgy connections being the most common cause I’d guess.
Are you planning on building a pack or are you purchasing it? If the former, ur in the right place and we can talk more about needed current, range, what kind of controller you’re using etc… If it’s the latter, pop over to the noob thread. Give a good rundown of all your compoent choices etc… and you’ll get some feedback. You can also discuss your needs with one of the builders on the trusted battery builder thread. They’ll be able to walk you through it.
A cell group displaying a lowest voltage when the entire pack is at a low SOC and the highest voltage when the pack is at high SOC would be indicative of a disconnected cell in the group.
Definitely planning to build! Probably wont be able to buy any components for a couple of months due to Christmas, but im beginning to plan things out. I will be making a custom enclosure too - should I be designing my battery around the enclosure or vice versa?
Ya co-sign w @rosco. Pick your deck and enclosure before you plan your battery layout and config. If possible, @Evwan gave you good advice on cell selection- 21700 are far superior to 18650s for both power and energy density. And go 12s. It’s just overall much better than 10s as you can pump out the same wattage with less heat on components. Molicel p42a are the gold standard right now but Lishen makes a very good cell at about 70% of the cost if that’s a limiting factor.
Can vouch for the lishen 21700LA cells, have 3 packs (1x 12s3p and 2x 12s6p) and they’re very consistent cell-cell and only perform about 15% worse than P42A.
I was able to catch this problem by monitoring the BMS app. As you can see I forgot to weld the negative side of the battery. In my opinion an app is a must have with esk8 batteries.
