This is the battery I’m looking at:
Again, I’m thinking of getting two and wiring them in parallel to up the Amps. If anyone can figure out from that how many cells are in there I’d appreciate it.
ok i’m starting to grapple with the concept a little easier now, but could you use stronger examples? I feel like strapping a literal jet to your back is basically just … you know… doing your own thing.
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so it’s a 10s2p or 10s3p battery (36v/3.6v=10 in series) and (5.8ah/2=2900mah or 5.8ah/3=1900mah). It doesn’t specify which Samsung 18650 cells it’s using so they are going to be pretty crappy.
Max discharge from the battery is 10 amps - really low! If it was made with Samsung 25r or 30q cells you are looking at 40-60A discharge on a 10s2p/10s3p battery.
This is going to limit your power so much that it doesn’t really matter what motor you pick. Even two in parallel is only 20A and still pretty wimpy. I draw (all battery amps) 40A at 12s single 6374 under normal acceleration and consume 17-20A to maintain 30mph. Like Hummie said, at 10s you will need even more amps to get to the same wattage.
My last run - battery set to 80A max:
EDIT: tldr; get a decent battery - maybe someone on the forums can build you one
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That would certainly be my first choice. The problem is then importing it into my country where, in addition to the customs tax on battery packs over a certain size (and this definitely qualifies), there’s a charge of something like 12% PER CELL! Hence my searching for a pack locally, custom or otherwise, preferably with a bms. what about this one?
A decent battery actually. Peak of 45 and continuous of 30 should give you a nice ride.
Actually - check the physical dimensions of the battery - 26ah seems really big. That’s like 10s8p or something? (80 cells)
It looks to be about 650 grams, and it’s really meant for a bicycle so it’s tall, about 38 cm. I’ll keep an eye on it though. There’s another one on the site that clocks in at 21 Ah, though everything else looks the same. Thanks for the feedback!
Are we looking at the same ad? I think it says 4.8KG?
That’s correct, I misread part of it earlier. here’s the product page:
There are ones with higher voltage and amps but they’re very expensive.
Considering your limited battery choice, I would kind of say you could go with 6364 motors but then again, for increased torque / kv rating, you might as well would need to choose 6374 motors, unless you do find ones in 6364 size, who can do 190kv or so.
Gearing might also play a big role, from what @Nowind has suggested, then 1:5 to 1:6 usually is a somewhat good value.
Im actually using 4.33 ratio but there are spots / places, where some torque is lacking even though im running 192kv single drive… (part of the reason might be single drive setup)
As for the motors / amps again… Well, 40A discharge battery wont give you the best performance… but if that’s all you got and have to work with, then I assume you will have to live with it…
21ah and 36v does sound quite a lot (in terms of capacity)
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Too bad u dont know any battery welder + that you got to pay tax even for single - individual 18650 cell import, sounds weird/crazy. Then you could just order the batteries and make custom pack.
Dual Motors, Dual Vescs and Dual Batteries… Now why didn’t I think of that?
Danger like speed is relative.
I think I know you, i’m from Israel too. I don’t think there is a tax on individual cells in Israel, but I know you have to pay 17% for anything above 75$. I ordered from nkon.nl (only one cell) they have good prices, and I didn’t need to pay tax for it, but I know someone from Israel who ordered 90 cells (from nkon too) and the custom gave him a hard time (I don’t know if he managed to get the cells). If you go for a mountainboard with 2 motors, I think the energy saving will be negligible if it even exists.
So would you do build something in that area?
I was sort of joking. Now that I really think about it, it would be better to build one 10s8p than to have two separate 10s4p packs . With 2 packs, you would need 2 bms’s and 2 power switches and 2 volt meters and what if they didn’t drain evenly.
Thats true well im make 1s4p packs with a + and - connection on each side to disconnect them if i ever need to change a set up or even a cell it would be easier for me. I just wanted to know about more distance. As for bms i would just use a bms to charge the pack once and make sure the individual packs are balanced after that i wouldnt use the bms anymore. I have all the supplies to make 4 complete electric boards with dual motors and vescs just havent done the battery for each. Im looking for options lol i appriciate your help @namasaki
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Your welcome and we are happy to share our experiences and any knowledge we can. Although I must say that I would never recommend charging Lithium batteries without balancing them every time. And I highly recommend using a bms for charging and discharging as well. Seeing that it offers some excellent benefits besides balancing your cells.
Well one of my thoughts was to just use the bms to charge the battery but not discharge simply carrying it with the charger and plug it in when i need to charge the batteries but if i use a bms in a 10s8p battery should i get a triple digit amp bms or just stick to like a 80a?
If you go with a Bestech bms 80a then it would be fine to discharge through. They can handle 80a continuously and peaks up to 200a+ I’m currently running two builds with them. Both have dual motors and Vescs. One is set with 60a battery max on ea. Vesc. The other is set a 50a battery max on ea. Vesc And I’m having no problem with either. The have thermal protection but they don’t seem to ever get hot. And I do climb a lot of hills.
17% above $75 is correct, and if you bring in anything in bulk they look especially closely. The rest of my info is from a forum that was last updated two years ago, that’s the most recent I could find. It could very well have changed since then. There are a couple of small companies in Israel who will do custom batteries on request. I could theoretically ask them to make a space-cell clone, but what it’ll cost is anyone’s guess… @Okami thanks for the info! I actually do know someone who has done some battery welding, I’ll try my luck with him. If all else fails, I suppose I can get a bunch of good battery packs from an rc hobby store and start wiring those.
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