Hi all, while I'm trying to sort the other issues with my bike I have a question about the battery, On the side it has a test button and 5 led lights but when its fully charged (charger green light on) and I press the button only 4 leds light up and I really cant remember if all 5 used to the battery voltage is 41.4volts. The LCD display (when I get it to turn on) shows a full battery any thoughts?

 

Thanks

Edited January 23, 20215 yr by Tazmantic

Led lights are just a gimmick they light up and can have nice colours, I only have one battery that does that with a nice shade of Blue. The only true indication of a charge is real time voltage reading.

Indicator lights are often 1 red and 3 or 4 green. They're a joke. Take no notice of them. Use a meter if you need to know the battery's voltage.

Thanks guys so does 41.4v sound ok?

Hi all, while I'm trying to sort the other issues with my bike I have a question about the battery, On the side it has a test button and 5 led lights but when its fully charged (charger green light on) and I press the button only 4 leds light up and I really cant remember if all 5 used to the battery voltage is 41.4volts. The LCD display (when I get it to turn on) shows a full battery any thoughts?

On your Joycube 360/11Ah battery: 5 LEDs should/will light if the battery is healthy (not worn) and fully charged. The charger LED turns green when the battery is MOSTLY full but it's still charging at <400ma at that point... it's balancing cells. You should leave it charging for an extra hour or two.

 

Press the battery button for >10 seconds to show state of health. All 5 LEDs will flash for 10 seconds if the cells retain >90% of performance, 4 LEDS >80%, 3 LEDs >70% etc. It's an assessment determined by cell age/total charge cycles.

Thanks guys so does 41.4v sound ok?

Not bad, but not particularly good either. Start panicking when it only charges tp 41.0v.

Not bad, but not particularly good either. Start panicking when it only charges tp 41.0v.

 

Oh what voltage is good.

Oh what voltage is good.

42.0v hot off the charger is good or 41.8v after it's had a chance to settle and balance. The voltage hot off the charger is a measure of how balanced it is. You can often restore balance by leaving it on charge for a long time after you get the green light.

 

Do you always charge until you get the green light?

On your Joycube 360/11Ah battery: 5 LEDs should/will light if the battery is healthy (not worn) and fully charged. The charger LED turns green when the battery is MOSTLY full but it's still charging at <400ma at that point... it's balancing cells. You should leave it charging for an extra hour or two.

 

Press the battery button for >10 seconds to show state of health. All 5 LEDs will flash for 10 seconds if the cells retain >90% of performance, 4 LEDS >80%, 3 LEDs >70% etc. It's an assessment determined by cell age/total charge cycles.

 

Ah ok mine just light up and only 4 so Ill leave it on charge for a while

42.0v hot off the charger is good or 41.8v after it's had a chance to settle and balance. The voltage hot off the charger is a measure of how balanced it is. You can often restore balance by leaving it on charge for a long time after you get the green light.

 

Do you always charge until you get the green light?

 

As I've mentioned before I didn't use it much and its been In storage for quite a while but I did charge till green light came on before storing. Though the charger is for the battery and says 42v it only seems to be producing 40v at the plug when disconnected from the battery (I've just measured) I do have a charger for a hoverboard that is 42v and producing 41.5v could I try that? the plugs are different (bike has 5 pins other has 3) but could I just connect the hoverboard charger + & - to the battery charging socket + & - or do the other 3 pins on the bike battery charger do something.

 

Cheers

The charger should show 42v when not connected, some have a voltage pot inside that can be adjusted.

The charger should show 42v when not connected, some have a voltage pot inside that can be adjusted.

Just took it apart and can measure

 

40v when not connected to the battery

41.4 when connected and led red (charging)

38v when connected and led green (stopped charging)

 

Have attached pic would the voltage pot be the one with the white on it to stop it being adjusted?

You can't measure the output voltage of that type of charger. It won't charge until connected to the battery and it'll get pulled down to the battery voltage as soon as it starts charging.

You can't measure the output voltage of that type of charger. It won't charge until connected to the battery and it'll get pulled down to the battery voltage as soon as it starts charging.

Ah ok but it was deff showing 40v not connected so I turned it up to 42v and checked voltages again but it still only charged for a few seconds at about 42 volts then went to green light and sat at 40v

Ah ok but it was deff showing 40v not connected so I turned it up to 42v and checked voltages again but it still only charged for a few seconds at about 42 volts then went to green light and sat at 40v

You mustn't try to adjust it when you can't measure it. You'll kill your battery and or/set your house on fire.

Thanks for the warning, so with this charger is there a way I can measure it? Would having it connected to the battery but having one of the charge wires disconnected from the charger board give me a true reading of the output?

You can only measure it while charging, which will give you the battery voltage as it rises, so keep measuring while charging. the only problem is that the battery will most likely switch off the charging when the first cell reaches HVC.

You can only measure it while charging, which will give you the battery voltage as it rises, so keep measuring while charging. the only problem is that the battery will most likely switch off the charging when the first cell reaches HVC.

That's what its doing then sits at 38v, had it on all night and its still the same so is it looking like the cells are getting tired? is it worth pulling the battery apart and measuring the cells individually?

 

Thanks

If you have one cell group hitting HVC before the others then the BMS shuts the charge process off, manual balancing is then required if more then a 0.1v out.

If you have one cell group hitting HVC before the others then the BMS shuts the charge process off, manual balancing is then required if more then a 0.1v out.

 

Is that an easy thing to do?

The only way of knowing if a cell group hits HVC before any others is to charge as far as poss then open the battery to get all 10 cell group voltages to see if a problem does lay there.

Thanks will try this later

Pulled battery apart as soon as charge stopped and all cell groups measured 4.15v

It looks then that the BMS has a 4.15v balance set for each cell group, so all looks/appears to be fine then. The manufacturer possibly looking at slightly longer cell longevity by not taking the charge to the max, the mah capacity lost is small and will be less then 100 mah one would expect.

Thanks so not to worry about the 5th led on the test button then though I’m sure it used to light, will have to see what happens after I’ve started using it again.

 

but one thing I’ve noticed as it’s 36v should it not have 10 cell groups (10s) and thus should there not be 11 wires on the balance plug mine only has 9 wires??

 

cheers

Edited January 25, 20215 yr by Tazmantic