Battery Volt Question

[Gmeng]

I have an observation about my battery and how long it will last fully charged:

On a full charge I get 55 volts I can run it down to about 40 volts and I lose all PAS and will turn off and on when I use walk mode.
Is this what other folks are encountering?

 

[Pokerdogg]

A fully charged 48v pack will be around 54.8 volt. 40 volt is when the Battery Management System (BMS) cuts off the power to prevent damage to the battery cells. However, a full discharge like that is stressful to the battery cells and is not recommended. Doing so repeatedly will reduce the life of the battery and increase the rate the battery capacity decreases. I suggest doing a search on how to preserve battery life.

 

[harryS]

There are two cutoffs. A 48V ebike controller has one, set at 40-42 volts. The battery BMS has one too, usually lower, triggering when the overall voltage is around 37-39 volts.

There is a third minimum, which is at the individual cell level, and this is the minimum voltage at which the battery cell will not be damaged, and also the number used by the cell manufacturer to rate the life/capacity. For the above battery, this number would be around 35 volts.

For a maker like Lectric, which uses a decent battery, I think you will get their advertised battery life if you run it til the bike shuts off. You're still way above the minimum operating conditions for the battery. Still, follow pokerdogg's advice, if you want to max out battery life.

 

[Bitmugger]

Everything HarryS said is spot on. I'd also add that don't fret if your bike doesn't charge to 54.6v exactly. Anything 53.5v+ is pretty common