Do's and Don'ts for e-bike battery care. What do you do to keep your battery performing at its best?

[rideronthestorm]

What’s commonly known with lipos is:
Store 66% or so
Never charge or discharge a better that’s hot ( recently used/ charged)
Fast charging causes more heat so it’s a bit of a degrading thing.

Thanks for the guidance. You mentioned LiPo batteries. Do these behave similarly to Lithium-Ion batteries which are generally fitted on eMTBs?

 

[Ark]

Thanks for the guidance. You mentioned LiPo batteries. Do these behave similarly to Lithium-Ion batteries which are generally fitted on eMTBs?

LIPO drop voltage quicker as the battery discharge and they aren't as energy dense

also they are pretty much guaranteed to catch fire when overcharged where as a Li-On will likely just swell a bit

Note how quick LI-PO goes from swelling to fire

 

[rideronthestorm]

Yep that's scary stuff Glad that ebike batteries use Lithium-Ion which seem safer than Li-Po.

The MBA article I linked earlier mentionned that "Expert consensus is that the worst thing you can do to your e-bike’s battery is damage it in a crash or purposely tamper with it... Crashes happen, but the battery packs are designed to protect the cells inside."

So, as far as battery care goes, besides avoiding to drop the battery, what should be done after a bike crash if the battery housing or battery cover has been hit?

Is the best practice to just replace the battery after a serious crash? Can a battery be tested after a crash for any internal damages that would make it unsafe to use over time? How to check it?

 

[rideronthestorm]

Regarding battery storage for weeks or months, keeping a charge around 50 to 70% seems to be the guideline.

But what if your battery is fully charged and you're unable to ride your bike and drain the battery to a storage-friendly charge.

Are there any electrical devices or tools that can be used to discharge a battery to an acceptable level for storage? Any such thing as a commercial battery dis-charger? Other thoughts?

 

[billium]

Actually, all you would need is a 99p 560 Ohm, 5 Watt resistor from Maplin if they were still around!

That would discharge at roughly 0.01 Amps and 2.5 watts - slow enough to not generate too much heat.
If you have 700WH battery and want to lose 300WH it would take about 120 hours or 5 days at that rate.

But having said that, I don't recommend it unless you know what you are doing - and by asking you probably don't!
Too much could go wrong if you connect the wrong terminals on the battery and they all have more than two.

Having someone ride the bike in Turbo for 15 mins is a quicker, cheaper and safer strategy.

 

[rideronthestorm]

Having someone ride the bike in Turbo for 15 mins is a quicker, cheaper and safer strategy.

Good advice, completely agree. Better be safe than sorry! Just surprised though by the lack of ebike chargers with a "storage discharging" function, since batteries have become such a prominent power source for our electric vehicles

 

[Alexbn921]

Is the best practice to just replace the battery after a serious crash? Can a battery be tested after a crash for any internal damages that would make it unsafe to use over time? How to check it?

It's protected by the frame and then it has it's own protective case and then the induvial cells are in metal cans.

A crash would have to eject the battery and significantly damage the case or snap the frame at the battery before I would consider replacing it.

If my battery was charger to 100% and needed storage, I would find some way to ride the bike, unless it's broken and waiting on parts or something. You could also swap the battery into a friends frame just to drain.

Using a resister is a good way, but I won't recommend it to someone that doesn't really understand what they are doing. Shorting the positive to the negative with the wrong setup could literally catch on fire or fry the battery.

 

[rideronthestorm]

If my battery was charger to 100% and needed storage, I would find some way to ride the bike, unless it's broken and waiting on parts or something. You could also swap the battery into a friends frame just to drain.

Good idea to swap the battery to another bike so it can be drained... safely

 

[rideronthestorm]

On the battery performance topic, I was wondering how to best troubleshoot battery health degradations?

For example, if you notice a significant drop in your riding range over a period of time (seeing less autonomy for the same ride over time), are there battery health checks that someone can do at home to help pinpoint an actual battery issue or just regular wear, which can obviously be expected as the battery ages.

With bosch batteries, I found that LBS/bosch dealers can run an e-bike diagnostic tool and check number of charging cycles, cell voltages, temps, etc.

I just had such diagnostic report printed for my bikes but couldn't figure out how to determine my battery health status, battery degradation % and what autonomy or range I should expect for a given assistance mode. Could this be calculated or estimated based on battery characteristics and diagnostic data?

 

[rideronthestorm]

It's protected by the frame and then it has it's own protective case and then the induvial cells are in metal cans.

A crash would have to eject the battery and significantly damage the case or snap the frame at the battery before I would consider replacing it.

It's definitely reassuring that batteries have many physical protection layers even down to the cell level. I suspect that a bike crash would have to be very serious to require a battery replacement.... and then probably also a bike replacement!