Moscow Plus Battery Bar Display Sketchy

blueskyca

New Member
I have about a dozen battery cycles on my bike and I'm still trying to understand the rationale for the battery meter indicator on the C7 display. During my first ride, I thought I would have 40+ mile range because the meter stayed at max 5 bars for the first 45 minutes. Then it dropped like a rock and I wound up with about a 22 mile range, limping home with 1 flashing bar.

About 80% of the time my home runs on a solar charged lithium power wall so I've been sensitized to battery voltage and load.

I've already measured the battery volt meter inaccuracies as others have done on this site, but the bar meter display stays at max bars all the way to 49.4V (indicated). This is about 3.8V per cell, which is closer to 50% or so capacity, assuming good cell balance. If I didn't pay attention to the voltage and jumped on my bike in the morning with 5 bars, but only 49.4V, I wouldn't get too far. I have a somewhat similar battery display on my electric motorcycle, but its 6 bar display is a little more sophisticated and linearly based on amp-hours consumed.

I realize that battery voltage under load and open circuit can be quite a bit different and are generally not a good capacity indicator, but I'm not impressed with the C7 battery bar display as a measure of remaining capacity. I can unobtrusively add a hall effect power and amp-hour meter, but how are others gauging their remaining capacity and range?
 

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jkvt

Member
If you're only getting 20 miles on a charge, unless you are going straight uphill the entire time, something sounds wrong with your battery. In the summer, without tire liners, I would get mid 50s at normal assist strength and PAS 4. Now, with tire liners and temps in the 40s and 50s I still do above 40.

I agree that the display waits a while to start dropping bars, but in my experience it's maybe closer to 30% capacity is drained... 49.3V I think (I think this is the correct spec sheet for the batteries: https://cdn.shopify.com/s/files/1/0...cr18650-ga-spec-sheet.pdf?6594479572025043155). I do find the voltage display more useful when I'm trying to decide how much capacity I still have left. At any rate, if you're only getting 20 miles on the Moscow Plus battery (16Ah), I'd call up Leon to get some help with that.
 

RJC

Active Member
I have about a dozen battery cycles on my bike and I'm still trying to understand the rationale for the battery meter indicator on the C7 display. During my first ride, I thought I would have 40+ mile range because the meter stayed at max 5 bars for the first 45 minutes. Then it dropped like a rock and I wound up with about a 22 mile range, limping home with 1 flashing bar.

About 80% of the time my home runs on a solar charged lithium power wall so I've been sensitized to battery voltage and load.

I've already measured the battery volt meter inaccuracies as others have done on this site, but the bar meter display stays at max bars all the way to 49.4V (indicated). This is about 3.8V per cell, which is closer to 50% or so capacity, assuming good cell balance. If I didn't pay attention to the voltage and jumped on my bike in the morning with 5 bars, but only 49.4V, I wouldn't get too far. I have a somewhat similar battery display on my electric motorcycle, but its 6 bar display is a little more sophisticated and linearly based on amp-hours consumed.

I realize that battery voltage under load and open circuit can be quite a bit different and are generally not a good capacity indicator, but I'm not impressed with the C7 battery bar display as a measure of remaining capacity. I can unobtrusively add a hall effect power and amp-hour meter, but how are others gauging their remaining capacity and range?
I have a Moscow 27.5 with the 48v 13AH battery and C7 display. On the flat on PAS 4 around 15 miles per bar on display.
 
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