52v battery on 36/48v controller doesn't work.

[NemoOmen]

Today I plugged in a 52v battery on a KT36/48ZWSRM-LL18 controller which manages a 500w hub motor.
The problem is that the display does turn on for an instant and then turns off. Then the display is dead until I re-plug the battery.
A very interesting fact is that once it turned on and I also had a good ride with the bike. Then I unplugged the battery to sort out if the problem was solved but no, it wasn't solved.

I replugged the 48v battery I substituted and it was okay, display was working and everything is ok.
The voltage of the 52v battery is 51.1v (not fully charged)
What can the problem be?

 

[NCC1941]

Sounds like you might not be making a good/consistent connection between the 52v battery and the controller.

51.1v is well within the normal voltage range for a 48v battery as well, so whatever the problem is, it likely has nothing to do with the battery being 52v.

 

[NemoOmen]

Yes, I don't think it's the battery. But I soldered an xt60 solidly. I find it impossible the problem is resulted to the connection.
Can it be related to the controller side?

 

[markz]

52V battery connection issue or a BMS problem.
Where did you get the battery from?
Can you open it up and see the + and - connection along with all the tab welds?

 

[NemoOmen]

It's a DIY battery. How do you think a connection problem would let the battery work at least once and give a constant 51 voltage?

 

[NemoOmen]

It's a DIY battery. How do you think a connection problem would let the battery work at least once and give a constant 51 voltage?

 

[wineboyrider]

High voltage cutoff on your controller? Or fried caps?

 

[999zip999]

A fully charged 52v battery is 58.8 v charge and completely balance the battery you do have a BMS ?

 

[markz]

Could be out of balance, where as soon as a load is applied the one weak cell just drops the entire pack low.

You need to start opening things up, visually inspecting things like the battery and the controller. Its also good to have spares so you could throw in another controller and hook up the battery and see what happens. Loose connections, corroded connections, weak cells, unbalanced pack, damaged wire insulation any number of problems could exist.

 

[999zip999]

State of charge you start at the negative end and you end up at the positive him. So 14s
Do you have a volt meter or multimeter ?
First voltage of battery
Then voltage of charger
Then all parallel groups of cells and write down paper the important part writing it down
1. 3.99v
2. 3.85v
3. 299v


14 Xxx volt
This is State of charge.
Then share.
Do you have a BMS ?
Please answer all questions.

 

[gnuorder]

I couldn't find info on the controller but my guess is it has over voltage protection and the time it worked, the battery wasn't at max voltage. Try discharging the battery some and see if it works then. post the specs of the controller.

 

[amberwolf]

The problem is that the display does turn on for an instant and then turns off. Then the display is dead until I re-plug the battery.

This means the power was disconnected from the controller, somehow. If power stayed constant to the controller, the display would not turn off, even if the controller itself shutdown for some reason (like an HVC, where a controller is designed to protect itself against overvoltage by not allowing motor operation).

If it's not battery related, then it would be most likely to be a display-to-controller connection...but the old battery working fine makes that unlikely.


If the battery has a BMS, then it could mean the BMS shut off it's output to protect the cells. That could be from a low cell group, or one with high resistance (bad cells, bad interconnects, etc) that causes voltage to drop under load. Sometimes a broken or barely connected balance lead will cause a BMS to trigger LVC or HVC.



If it doesn't have a BMS, then it would have to be a connection problem, the most common of which is at the main output connector, but could be any series interconnection anywhere between the main + output on the main connector, to the main - on the same connector.

The most likely thing that causes a problem that happens intermittently is a connection.

If the pack worked fine at one time, and this is a new failure, then whatever happened to the battery between now and then is the likely cause.

If the pack is new and has never been used before, then it is likely there is a problem in the battery somewhere, anywhere including the output connector, wiring, cells, interconnects, etc.

 

[NemoOmen]

The problem is that the display does turn on for an instant and then turns off. Then the display is dead until I re-plug the battery.

This means the power was disconnected from the controller, somehow. If power stayed constant to the controller, the display would not turn off, even if the controller itself shutdown for some reason (like an HVC, where a controller is designed to protect itself against overvoltage by not allowing motor operation).

If it's not battery related, then it would be most likely to be a display-to-controller connection...but the old battery working fine makes that unlikely.


If the battery has a BMS, then it could mean the BMS shut off it's output to protect the cells. That could be from a low cell group, or one with high resistance (bad cells, bad interconnects, etc) that causes voltage to drop under load. Sometimes a broken or barely connected balance lead will cause a BMS to trigger LVC or HVC.



If it doesn't have a BMS, then it would have to be a connection problem, the most common of which is at the main output connector, but could be any series interconnection anywhere between the main + output on the main connector, to the main - on the same connector.

The most likely thing that causes a problem that happens intermittently is a connection.

If the pack worked fine at one time, and this is a new failure, then whatever happened to the battery between now and then is the likely cause.

If the pack is new and has never been used before, then it is likely there is a problem in the battery somewhere, anywhere including the output connector, wiring, cells, interconnects, etc.

Today I tried the battery pack on a 48v e-scooter. Everything worked fine.
So the issue is certainly with the controller, but I cannot understand which. The battery voltage was 51.1 volt so for a rated 36/48v controller it should be still a normal voltage, isn't it?