Help identifying problem

How-Tos & Esk8 mechanics Esk8 Mechanics
#1

Hi guy thanks in advance for your help I appreciate it.
so after 3 weeks of rain and no driving I charged up my board to go on a ride. It showed full battery for a sec then went instantly to half and once Ive hit the gas a little the remote indicated low battery and after 3 sec it turned off.
So I disconnected the battery and charged it till the green light +30min and tried again.
This time it stayed at full battery until I accelerated.

I’m pretty sure it’s the battery at that point but the voltage coming out of the battery looks totally fine. And one of the hub motors got a lot of resistance probably due to longer pause.
Could it be that the motor is causing to much power draw so the ESC or bms shuts of?

You can see it in the video how much difference between the 2 wheels is, wd40 didn’t help.
Video was taken while charger is connected

Even while on charge the power cuts out on the higher settings.
Could the charger even be broken? It switches from red green light the whole time now

Ist a Prebuild Apsuboard v5
2x 350w motor I think
14s2p battery weird size I know they say it’s to combat voltage sag and make up for small motors
ESC generic ling yi esc
Got 120mm cloudwheels since 300km that couldve put more strain on the batteries

#2

Definitely sounds like a dead cell in a battery pack. If you are not familiar with batteries, not much you can do.

What I would do is to open up a battery and check each series for voltage. That should give you a hint what cell/s are done.

DO NOT TRY THIS IF YOU DO NOT KNOW WHAT YOU ARE DOING. SEND IT TO SOMEONE WHO DOES

4 Likes
#3

Sounds more like a loose series connection to me, once you pull current it just dies.

Could be alot of things tho. BMS crapping out, sad cells etc.

3 Likes
#4

Yeah well 1500km out of a 350€ board is not too bad I guess, it’s winter now anyway

1 Like
#6

I second this.

3 Likes
#7

If there’s any kind of plug like bullets or an XT90 in there between the battery and ESC you can also check for charred contact surfaces. Had a racing drone get similar symptoms to this by smoking an XT60, dies once you try to run it up.

1 Like
#8

I had oxidized xt 60 plugs but I removed them all together except of 1.

Ill have to get a multimeter and check the battery pack or I just wait till next season and get myself a proper one

#9

Do you have a photograph of that?

#10

Just flux them brah

#11

I can’t believe what im reading. @zZoKo @ShutterShock you guys better get here.

3 Likes
#12

No I removed them an soldered them together directly

#13

What am I missing?

#14

I had a thought today.
Since one of the wheels is not freelyspinning properly, possibly due to moisture/water.
Could it be that the motor is shorting and that’s causing the problems?

I don’t need to know if that’s my problem just if it’s possible that this causes the the battery problems,since the voltage coming out of the battery is 58,8v(14s)

#15

You can do a BLDC hand test to check for that, but it doesn’t sound like it to me. I’m not familiar with that ESC though.