Battery not charging all the way?

[batmick1]

Today was the fourth time it happened to me and I wanted to see if anybody had an idea of what could be wrong (if anything) and what to do about it.

Sometimes, like today, the bike (2016 Haibike XDuro Trekking RX) charged overnight and when I start my ride the display is off and the charger is inactive, just like when it is done and the battery is full. The charge indicator on the display shows all bars when I start.

I ride my commute almst every day and have a very good idea of when and where the charge indicator should go down a bar. I average about 5-6 miles per bar at my regular pace. Today for the fourth time the first bar dropped after only about 3.5 miles. The bars after that were back to my usual 5-6 miles. It is almost like the battery did not charge all the way but just enough to fill all the bars. But this doesn't happen consistently. After the next charge it will likely be back to normal.

Has this happened to anybody else? Any suggestions?

Thanks!

 

[rich c]

Take off the display and clean the contacts throughly with denatured alcohol and a cotton swab.
I don't know what this means. What do you mean when you start riding the charger is inactive? "charged overnight and when I start my ride the display is off and the charger is inactive".

 

[batmick1]

Take off the display and clean the contacts throughly with denatured alcohol and a cotton swab.
I don't know what this means. What do you mean when you start riding the charger is inactive? "charged overnight and when I start my ride the display is off and the charger is inactive".

Thanks for the quick reply.

I mean that when it is plugged in but done charging, the unit turns off/goes to sleep. So when I come in in the morning I need to unplug the charge cable or press the power button to turn it back on.

 

[rich c]

You are turning on the charger, still plugged into the battery, after it was fully charged over night? Why? The battery is fully charged when it shuts off. You may be damaging or shortening the life of the battery by double charging it. I've not found it necessary to check the voltage of my Bosch batteries, but when anyone says they have battery trouble, they need to use a multimeter and measure the actual voltage. Not look at the pretty lights or bars.

 

[batmick1]

You are turning on the charger, still plugged into the battery, after it was fully charged over night? Why? The battery is fully charged when it shuts off. You may be damaging or shortening the life of the battery by double charging it. I've not found it necessary to check the voltage of my Bosch batteries, but when anyone says they have battery trouble, they need to use a multimeter and measure the actual voltage. Not look at the pretty lights or bars.

No, sorry I expressed that wrong. I plug the bike in when I come home in the evening. It finishes charging some time later that night. When I go to start my ride to work the next day I unplug it and pack the charger in my saddlebags to take with me. At that moment, when I pull the charge plug, the Intuvia unit turns on and shows full bars. That's what I meant.

And how would measuring the voltage tell me how much juice is actually in the battery? Aren't they built to have a steady DC output for as long as possible.

 

[rich c]

A fully charged pack measures above the nominal rating on the pack. A 36v pack will measure 41 volts when fully charged and around 32 volts when the BMS shuts it off.

 

[batmick1]

Good to know. Thanks!

I will check this out. I'll also clean the contacts on the head unit. Never considered those but it makes sense.