I’m just starting to dip my toe into the DIY efoil world hear, so forgive my ignorance. Has anyone tried or does anyone know if an ebike battery pack would work to power the typical motor setups you use? I ask because they are relatively cheap, durable and waterproof. The specs of a typical one on ebay are below. Its selling for $185.
Item Technical Data Note
Battery Model EBB-048130HL1-2-US04
Voltage 48V
Capacity 12.5Ah
Weight
Approx 9.26lb
Energy 600Wh
Cycle Time 1000+
Cells High power 2500
Discharge Standard Current 10A
Max. Current 20A (Max. 30Sec.)
Protect Current 50A
End Voltage 39V
Charger Charge Voltage 54.6V
Charge Current 2A
Brand Unbranded
Weight Approx 1.54lb
Packing list Battery 1
Discharge Connector 1
Charger 1
I am using two Ebike batterys in paralel. Each is capable of 30A Standard Current.
60A is enough for my 6384 Build. It works perfectly for me. But your 10A is way too low…
Discharge current is too low, for efoil you need more like 100A continuous, 150 peak.
Really? 100A to 150A? I built an electric skateboard last summer running two 6384’s. In doing research for that, it seems to be that those batteries tend to put out 60A to 90A.
If I wanted to calculate the discharge rate of a battery pack, I would multiply the discharge rating of the individual cells I’m using (25A) by the number of parallel cells? So a 14S10P pack would have a discharge rate of 250A?
Yes, that is correct but it is good to have some margin, if you have a look at the discharge graphs of a cell, you see that capacity is lower if you discharge with higher current. The cels also get quite warm if you discharge them at the current limmit.
Would you be able to tell me if the pack I outlined above would be a good fit for this motor?
The cells actually have a continuous discharge of 25A and a max of 35A I see that the “Max Current” of the motor is 300A. Does that mean it’s max draw would fall right in the middle of my battery’s range? I just want to make sure I’m comparing the correct specs. Thanks.
The ebike battery you outlined above likely has a bms that will limit the max current. So while the battery cells themselves might be able to put out that much current the pack as a whole cannot without getting rid of the bms.
If you put a suitable esc between motor and battery, it schould work, if the pack can deliver enough current. I would not buy the prop, just the 120KV motor, the prop is too big. Have a look in the forum, plenty of working examples. Spend some time reading it, before you order stuff.
Sorry for the confusion. When I said “the pack above” I meant a 14S10P pack made with cells that have a continuous discharge of 25A and a max of 35A that I mentioned in a follow up comment. That would make the total 250A to 350A. With the MTI65162 having a max discharge of 300A, that would put it right in the middle. This would be a good fit right?
Agreed. I heard in the forums that the Maytech prop is no good. I’m thinking of a Flight prop or a Flying Rodeo. I’d love a folding prop but they’re so expensive.
Both work but there are more suitable propellers with 6 or 7“ pitch available that fit the 120KV. For the 100KV Motor you need 8“ pitch to get decent speed on 12S. The one with 12mm shaft and M8 thread is most compatible with available propelllers.
See here: Newcomer's build [Ger] + 2nd one - #250 by Ackermann
There are two choices with the 120KV. One is 12mm and M8 thread. The other is 12mm, M8 thread and it’s splined. Having the choice, I’m assuming the splined version would be compatible with even more propellers. Am I correct?
My mistake, I had thought you were referring to the original ebike battery. As long as the rest of the wiring and electronics (if any) in the battery can handle that current then what you say sounds right. As mentioned earlier, the higher the current per cell the warmer the battery will become. Nice if you have some margin!
