for a 4p set that should work ok. I saw Jehugarcia (Electric VW Van guy on Youtube) really fight making a huge pack, but saw a great response from the vruzend guys:
Looks like a cool system and worth trying if you don’t want to solder/spotweld.
Personally when i build my boards i like low profile/thin lipos and run a few 8s setups (one is a bit bulky, but usually thinner). Those 5Ah 60C packs look nice, but a bit thick, and 4 of them on a board will be super heavy (about 4.5 lbs). I really like the 8Ah 30C lipo and have a set that are nearly 2 years old still working well. yours selected is 39mm thick, the Zippy 8Ah 30C are 35mm - so close enough to be the same besides capacity. I’d run 2 not 4.
Did you read up on range and watt hours (Wh)? 10Wh = 1km (approx - rider weight, hills, fast acceleration will all impact - but good ballpark estimate). Wh = V * Ah. So your 8s (4.2 * 8 = 33.6v) 5Ah… 33.6v * 5Ah = 168Wh = 16.8km/10mi.
If you go lipo get a good charger. The iMax b6ACv2 (non clone be careful) is a good one. Also impressed by the iSDT Q6 (but you need AC->DC Power supply).
Thanks for all the info, I really like that slim 8ah battery (I found it on Hobby King) but 3 or 4 reviewers were saying that they puff up after multiple uses. There’s no reviews on the ones that I linked though… If I use a good charger they shouldn’t misbehave right?
I think I might save 18650 cells for later if I really like the hobby down the road… Too involved for me right now. Thanks for all the info and tips - people like you make this awesome community what it is.
Clayton
Still suggest you read and read and read. Build something that copies another build - highest form of flattery. And you won’t be blazing new trail with untried components… not a great idea on a first build.
18650 are really nice and i’m slowly getting into them now myself. BUT you have to really know your current consumption needs (how many amps do you really use when you ride) - or over build it (which gets big/heavy and costly $$$).
As for the Zippy puffing - i’ve had a few puff (none of the 8Ah 30c packs - but others). Hit/Miss sometimes. The worst for me were the 10Ah 10c multistars (don’t recommend - though i have my brother riding some since i grabbed them on sale and didn’t use).
Best way to avoid puff (besides some bad QC from factory) - is not to over charge, or over discharge. And if sitting for a while - drop them to storage voltage not fully charged sitting. And a good charger. Another great measure of their “health” is to measure and mark their new internal resistance, and periodically measure to see how they are doing. Look for cell drift and occasionally do a few discharge/charge cycles if they get too far out of wack (sometimes will bring them back).
I try to find chargers that all will measure IR as a result - super handy.
OR you can do some fun measurements and math:
Fun with FLIR!
Geekiness fun w/ FLIR aside - it just takes a multimeter, resistor, and some math. Measure unloaded voltage, then voltage under load (i used a 5.7ohm 10w resistor), and get voltage drop under load - math math math and you get resistance in milli ohms.
a good tutorial on instructables:
A simpler youtube video on this i followed:
Kinda fun - or even better i’d get a charger that measure IR!
