Bike stops with 5% battery left

[pmac]

I've got a Focus Sam2 2020. When the battery gets to 5% the motor stops working. Is there any way I can put that last bit of juice to work?

 

[ThierryGTLTS]

I've got a Focus Sam2 2020. When the battery gets to 5% the motor stops working. Is there any way I can put that last bit of juice to work?

Probably to protect the battery because Li-Ion don't like to be fully depleted.

Some batteries reduce the current when about 10% leaving, and stop at about 3 to 5%.

And it's not a god idea to try to use it to 0%, it'll reduce the lifespan significantly.

Have a Nice Day.

Thierry

 

[pmac]

Probably to protect the battery because Li-Ion don't like to be fully depleted.

Maybe, but its common practice that software shows 0% when the batter is depleted to its safe range. The same goes for 100%. There not much point of showing 5% if it can't be used.

 

[GrahamPaul]

Maybe, but its common practice that software shows 0% when the batter is depleted to its safe range. The same goes for 100%. There not much point of showing 5% if it can't be used.

I read somewhere on Bosch's website or in their manual that this is done so that you can still use lights for a few hours. It was considered unsafe leaving the rider in the road with no motor and a total blackout. (Don't forget that the biggest Bosch market is commuter bikes which come with lights plumbed in).

 

[rocky yeung]

I have a post here that you may be interested to read.

2018 Specialized Turbo Levo battery cut out at 4th LED

Bike model : 2018 Specialized Turbo Levo FSR COMP 6 Fattie battery Problem : battery cut out at 4th LED, 1st LED being the red lowest one. Repair warning : At your own risk. Careless mistake may short circuit that may cause sparks, fire and then explosion if ignored. How it happens : Pre...

www.emtbforums.com

My Specialised Turbo Levo battery shows 0% left but the battery is not 0V ! Completely drain to 0% does not harm to the battery if it is really healthy. But you are adviced to charge it back asap, well within 24 hours is acceptable. Please refer to your own bike battery management system scheme.

 

[Tooks]

I have a post here that you may be interested to read.

2018 Specialized Turbo Levo battery cut out at 4th LED

Bike model : 2018 Specialized Turbo Levo FSR COMP 6 Fattie battery Problem : battery cut out at 4th LED, 1st LED being the red lowest one. Repair warning : At your own risk. Careless mistake may short circuit that may cause sparks, fire and then explosion if ignored. How it happens : Pre...

www.emtbforums.com

My Specialised Turbo Levo battery shows 0% left but the battery is not 0V ! Completely drain to 0% does not harm to the battery if it is really healthy. But you are adviced to charge it back asap, well within 24 hours is acceptable. Please refer to your own bike battery management system scheme.

If your bike battery ever got to 0v, it would be screwed and beyond saving.

When your bike is showing 0%, it’s battery is still at 30v or so. Lipo’s are 4.2v per cell when full, and 3v when depleted, but many BMS will not let them go that low for pack longevity reasons. They will go lower, but not without damage which is why the BMS manages things, I think my focus is 34v.

There are 10 ‘cells‘ (which may be multiple batteries in parallel making up a cell, not just single batteries) in a typical e-bike battery, the BMS will manage them individually (if It’s a good one), it may call time on the pack discharge if it detects one cell is at the lower limit rather than deplete the pack to the lower limit (at least 30v). This may show as having a % left in the display.

I’d charge it to 100% and let the BMS balance the cells out, that might help.