Range reduces overnight

[steve_sordy]

A year ago I used to get 44 miles range, now when I charge my bike the night before I ride I usually get 41 miles (it's on a Focus with the 378Whr battery). Overnight the range drops to 38 miles. I tried charging again, but the charger won't charge, just stays steady green instead of blinking to indicate charging.

I can't say as I have noticed a range problem on the ride because I seldom go down to the wire on battery life. Just interested..... Is it a pre-cursor to a more serious fault, nothing to worry about.......?? Comments would be appreciated.

 

[R120]

I am always slightly suspicious of the data when a brand is using a non Shimano battery with a Shimano motor - who does the calibration fo the system to judge the range, is it a common Shimano BMS in the battery?
Really I am asking more questions rather than providing answers, but it wouldn't surprise me if its a reading of the battery issue rather than an actual problem, though range will replete over time.

 

[Rusty]

Could be a cell issue - you have an app that connects to it?
Should show battery health if so.

 

[Zimmerframe]

A year ago I used to get 44 miles range, now when I charge my bike the night before I ride I usually get 41 miles (it's on a Focus with the 378Whr battery). Overnight the range drops to 38 miles.

It's supposed to adjust and learn to a degree .. maybe it's just worked out that you're a lazy bugger in the mornings ?

 

[Gary]

I used to get 44 miles range

You realise it's just an estimated number based on a rider that isn't you riding round a flat loop with one tiny little climb each lap?
Just ride your bike and ignore the (fairly) pointless range reading

 

[andytiedye]

"RNG" = Random Number Generator

 

[Changleen]

Ignore it. It’s trying to be clever based on recent experiences. Useless in real life. W/h remaining would be better.

 

[GrahamPaul]

I play a game with my range estimation: how big a variation I can get riding in ECO. So far it has gone from 212km down to 40km within a couple of kms, then back up to 121km.

You know it's a dumb algorithm when you get a lower range from having ridden with the motor in the OFF setting than riding with the motor in ECO...

 

[Dan63]

The range is estimated based off current level of charge, power mode selected and data from recent usage. The range estimate is going to change based on the riding you have done in the last 5km or so.

 

[04fuxake]

Couple of thoughts based on having an EV.....

• The battery may be degrading a bit so after a year of regular usage and cycles, the max range will fall slightly
• The estimated distance is probably based on how you last rode it. I know our EV will have varying amounts of range each morning based on how hard or eco it was driven the prior day.

 

[steve_sordy]

Thanks for your many replies.
Most either say that the range falls anyway the more I charge the bike, or changes with how I ride the bike, (both of which I was aware of) or just take the piss (and I'm OK with that). But my main question was why after having charged it and got a 41-mile range forecast, that it drops to 38 miles overnight just sitting there switched off. It hasn't done that before.

 

[Rusty]

Refer my post

 

[MattyB]

My experience of lithium packs from RC use is that many will (after a decent number of cycles) start to exhibit a more pronounced “relaxation” after coming off charge and being left a few hours; often they will self discharge 0.05-0.1V/cell, then stabilise. I don’t know the chemical reason for this (presumably it is something to do with deposition occuring at the anode) but it might explain what you are seeing.

This tendency will vary pack to pack depending on how they have been treated (storage SOC, storage temp etc), but this should only have a small (if any) effect on your real world range, at least up to the ~100 cycles point. YMMV (literally! ?)

 

[steve_sordy]

@Rusty I had seen your post (which is why I referred to "most posts...."). Thanks for the response, but I don't have an app that gives any battery stats. It's a Shimano battery, so if anyone is aware of an app that gives detail battery stats, please post a link. I currently use the E-Tube app now and again to load updates.
@Matty B Thanks also for your response which appears to provide a convincing explanation for what I'm seeing. I haven't experienced a range reduction, because what I do is different every time I go out, so it's difficult to tell. I certainly haven't been inconvenienced by it. From what you say it is not a serious problem or even close. But I will keep my eye on it. I have another 9 months of warranty yet.

 

[Rusty]

Thanks for the response, but I don't have an app that gives any battery stats. It's a Shimano battery, so if anyone is aware of an app that gives detail battery stats, please post a link. I currently use the E-Tube app now and again to load updates.

You LBS can plug in their app and tell you - most do this as a free service in my area. Or you could try Steps Unlocker

 

[steve_sordy]

You LBS can plug in their app and tell you - most do this as a free service in my area. Or you could try Steps Unlocker

Thanks @Rusty

 

[RickBullotta]

@Rusty I had seen your post (which is why I referred to "most posts...."). Thanks for the response, but I don't have an app that gives any battery stats. It's a Shimano battery, so if anyone is aware of an app that gives detail battery stats, please post a link. I currently use the E-Tube app now and again to load updates.
@Matty B Thanks also for your response which appears to provide a convincing explanation for what I'm seeing. I haven't experienced a range reduction, because what I do is different every time I go out, so it's difficult to tell. I certainly haven't been inconvenienced by it. From what you say it is not a serious problem or even close. But I will keep my eye on it. I have another 9 months of warranty yet.

Steps Unlocker or the eTube windows app with an SM-PCE1.

 

[steve_sordy]

Steps Unlocker or the eTube windows app with an SM-PCE1.

I have the e-Tube app on my phone, but what is an SM-PCE1

 

[RickBullotta]

I have the e-Tube app on my phone, but what is an SM-PCE1

USB to eTube adapter box and cables. For use with the PC eTube app which includes lots of diagnostics including battery diagnostics.

 

[steve_sordy]

USB to eTube adapter box and cables. For use with the PC eTube app which includes lots of diagnostics including battery diagnostics.

So it comes with extra software not included in the e-Tube app on my phone? (To get the battery diagnostics....)

 

[RickBullotta]

So it comes with extra software not included in the e-Tube app on my phone? (To get the battery diagnostics....)

Yes. But Stunlocker has the battery diagnostics data as well, and you can use Bluetooth to connect rather than buying the extra adapter.

 

[steve_sordy]

Yes. But Stunlocker has the battery diagnostics data as well, and you can use Bluetooth to connect rather than buying the extra adapter.

Great stuff! Very helpful, thanks!