Battery shuts off...

[Randee]

Hello everyone! Randee here, an e-bike enthusiast from Manila.. i built a standeebike and just finished a week ago.. im having a problem with the battery (DIY).. after few minutes of running the bike, it shuts down to 0 volt... then after few minutes it returns to 26+ volts.. and repeatedly shuts off again after few minutes.. anyone experienced it here?

 

[tomjasz]

DIY batteries can be a nightmare. Building your own without experience can be fraught with downfalls. I’d get Micah Toll’s battery book and sort your battery issues. Hopefully you’re not using mismatched salvage fells?

 

[Randee]

All cells are new and with same mah.. i used BMS too..

 

[Randee]

I even sorted out all cells for individual voltages and group it together... I checked the BMS wirings and found it ok.. I'm still wondering why the battery shuts off after 1 to 2 minutes of continues running the bike... do installing a capacitor in parallel with the battery helps?.. please advise..

 

[tomjasz]

Apparently you went off without much research. Those cells, Ultra FIre are absolute junk. Know throughout the DIY battery scene S pure garbage. Then it appears you soldered Nickel strips, another bad idea. That is a battery fire waiting to happen. I’m out. I’m sorry but I won’t be a continuing part of this potential disaster.
The please do not charge without closely monitoring and in some sort of protection. Metal trash can with lid and handle or an ammo can.

 

[Gionnirocket]

Soldering is not an option as the heat damages the cells.
This is a case where you take this mess to the recycling center and do some more homework before you start again...
Or better yet, just buy a new battery and enjoy life as this is not a diy project without proper tools, experience and technique.
Live & Learn as they say
Sorry my friend.

 

[tomjasz]

There is one solder technique that can work using Goot Wick. A good solder station and quick work required IME.
I’m starting to use these.

 

[tomjasz]

This was a Micah Toll failed kit. But an interesting technique. My sample has never been finished. We’ll see how my 100 5 year old batteries, stored in 50F, test.

View attachment 85398

 

[Gionnirocket]

There is one solder technique that can work using Goot Wick. A good solder station and quick work required IME.
I’m starting to use these.

Perhaps the NESE... if the quality is there.
I'd stay away from soldering.. All it takes is 1 poor/overheated connection.

 

[tomjasz]

Perhaps the NESE... if the quality is there.
I'd stay away from soldering.. All it takes is 1 poor/overheated connection.

NESE works really well and excellent parts. 3D .stl files are free to print your own case.

while I’m not a solder fan the goot style can work but only with good solder techniques to reduce heat. Frankly I’m more comfortable with the goot packs thenUPP and other China builds. I’ve tried every kit. I have spot welders but shouldn’t use them with my pacemaker. My battery repair tools are being sold off soon. Enough. It was fun and enlightening. But building isn’t much of a saving given the overhead. And risks.

 

[Gionnirocket]

NESE works really well and excellent parts. 3D .stl files are free to print your own case.

while I’m not a solder fan the goot style can work but only with good solder techniques to reduce heat. Frankly I’m more comfortable with the goot packs thenUPP and other China builds. I’ve tried every kit. I have spot welders but shouldn’t use them with my pacemaker. My battery repair tools are being sold off soon. Enough. It was fun and enlightening. But building isn’t much of a saving given the overhead. And risks.

I haven't looked into it much as my needs do not warrant it.. But just some preliminary research told me to just buy a battery pack... Especially as I only needed the one.
This is where the internet hurts many novices. Not doing enough research and going by a youtube or one off build thread. You hear how great it is... But there is never any follow up or how it is working 6 months down the road.. and what can go wrong is never mentioned.
I'm not saying it's hard to build a battery if you have some experience... But you sure as hell better do it right using solid techniques.

 

[Gionnirocket]

This was a Micah Toll failed kit. But an interesting technique. My sample has never been finished. We’ll see how my 100 5 year old batteries, stored in 50F, test.
View attachment 85399


View attachment 85398

Isn't this another Mikah kit?
It doesn't look to have gained much acceptance.

 

[tomjasz]

You hear how great it is... But there is never any follow up or how it is working 6 months down the road.. and what can go wrong is never mentioned.

No so in the build groups I read and post in. You have no interest. I get that. That doesn’t mean there aren’t successful builds. This isn’t the right forum IME. Not for battery building.

 

[tomjasz]

Isn't this another Mikah kit?
It doesn't look to have gained much acceptance.

Oh FFS. Isn’t that what I wrote? Whose looking for acceptance? That was 5 years ago. It went nowhere. The pricing was the issue for most. Look back and you’ll see I typically discourage building DIY batteries!

 

[Randee]

Thank you Guys for your insights... I will try to look for another good cells and prefer doing it it again.. DIY is my life..