Went out to test my efoil today, had a great ride for 10 minutes, then started to lose power. Opened up my electric box, and check out the batteries…
They are upside down in the box because of a funky construction hiccup, but that should not matter, right? Also they get a lot of slamming down because I suck right now…
What in the world happened? they are basically new.
PS
Also, any rec’s for the latest and greatest batteries? 
Need to get new ones asap! I have a Seaking 130A 6-12S ESC.
Probably pulling to much current for them to handle, what they suffer from is electrolyte decomposition. I See it says 100C discharge but its probably no where near that value in reality. For multiple stop starts you will pull max current each start and in my experience with such a small AH rating the battery will have a bad time fast if its a cheap lipo. Also they def don’t like to be bounced around lol. The orientation of the lipo doesn’t matter.
Some questions to help understand the situation better:
Did you connect them in parallel or series?
What dose your battery enclosure look like?
What did you charge them with and to what voltage?
What is your low voltage cutoff set to?
How many amps is your max current draw?
Most people seem to use the Samsung 30Q cell - myself included, but any decent discharge cell will do
thanks so much for the help!
Connected in series
Batteries and etc are in a waterproof pelican case.
Charge them with Onyx KS80 Lipo charger, to 22.2 volts each
I don’t know where my low voltage cutoff is or what it is set to…
Don’t know the amps draw- assuming 130A since that’s what my esc is rated …?
The last thing i want to do is solder a bunch of batteries together… is there a battery out there this group likes that is already pre-manufactured? I saw several options like this one:
or
Would one of those suffice?
thanks!!!
BTW, it says “100C” on the sides of those batteries. Can I assume that is a load of fish poop?
I think you should first check the motor functionality, ESC, maybe you have the wrong propeller (large diameter or high pitch).
You probably have Lipol batteries very popular. However, if I recall correctly, Lipol were invented to be light weight, and only for use in laptop, RC models, etc.
I think all the best builds I’ve seen here use Li-ion. Also, my e-bike (from the world’s most famous company), e-scooter and other workshop equipment use Li-ion, no problems to date - maybe you should finally switch to this proven workhorse too :-).
motor is solid, prop is good - they have been functioning perfectly so far.
Do you have a recommendation for a Li_ion battery? preferably one prebuilt so I don’t have to make one of those daunting multi-cell cases…?
In my build, I am planning a larger number of parallel cells (and therefore a larger weight of the whole set), but with a slightly lower capacity than recommended here. However, I want to achieve lower discharge currents per cell and therefore lower heating and longer life. This solution is probably not suitable for your needs.
I’m sure someone here will advise you soon, there are a lot of smart people here.
Most people switched over to LiIon packs. I have both, a LiIon pack and some LiPos that I still use as a second battery but I would not really recommend them. They work but I can only get about 14-15 Ah out of them. It is Turnigy 6S1P 20Ah from Hobbyking. Mine are still fine but I only discharge them @max 100A and only to 3.6V. They tend to puff if you discharge them with too much current, especially when they are getting close to empty. You can find some reports about that in the forum.
How can you adjust the discharge amperage? I have a Seaking130A esc and I don’t see that option.
Would this battery be sufficient? (the 20A is on backorder)
You can’t limmit current with a seaking, only indirectly through the prop. Smaller prop or less pitch means less current. With a vesc you can limmit max motor and max battery current but if you set it too low, you don’t get on the foil. Depends on your setup and your weight, I set max bat current to 100A but in normal conditions on a lake I could reduce it to 80A.
Those batteries are more like 6C (experience from other members) so with 12AH you get 72A continous. Could work but close to the limmt.
