Shimano Battery Life Poll

[nasamorpheus]

Battery One (model bt-e8035 504wh)
1) # of charging cycles = 32
2) remaining capacity = 85%
3) charger = Mainly e6002 slow charger, but use e6000 on weekends.
4) age = 5 months

Battery Two (model bt-e8035 504wh)
1) # of charging cycles = 20
2) remaining capacity = 87%
3) charger = Mainly e6002 slow charger, but use e6000 on weekends.
4) age = 4 months

Both batteries fell to 90% remaining capacity at about 10 cycles and 87% remaining capacity at about 20 cycles. Both batteries are stored at SoC between 40-60% then usually charged to 100% the night before.

I suspect my slow charger (e6002) as the problem as the slow charger charges faster (14% per hour) than my fast charger (e6000) between 80-100%. Given that I use both chargers it is possible that the fast charger is degrading the batteries faster.

What a crap batteries are that.. I don't understand why you guys just don't go best of the best and that is Bosch. You really believe there is something better in the market? I have 100 cycles and no noticeable battery capacity changes.

 

[routrax]

Not sure which model, it's a 504w external one.
No special battery yoga, charge it until it's full, ride it until it's flat.
It's my second/spare battery, purchased July '19.

 

[Milan]

What a crap batteries are that.. I don't understand why you guys just don't go best of the best and that is Bosch. You really believe there is something better in the market? I have 100 cycles and no noticeable battery capacity changes.

Yeah, you are right, but you do not always buy a bike just because it's got the best battery or do you? I bought mine because it's constantly been a great ride....never expected that they've got faulty batteries and that Shimano would treat me like a p.....o.....s when I tell them they've got a problem.

 

[routrax]

Maybe it wasn't my second battery! Hard to tell, they're so alike...

This is a great way to keep your battery in good condition.

 

[nasamorpheus]

Yeah, you are right, but you do not always buy a bike just because it's got the best battery or do you? I bought mine because it's constantly been a great ride....never expected that they've got faulty batteries and that Shimano would treat me like a p.....o.....s when I tell them they've got a problem.

When you buy regular bike you search great ride, when you buy ebike you search good ride and realibilty (well at least I look for that things and I dont understand why you would choose Shimano over Bosch, maybe for display and controls..) . You can get good ride from bikes with different motors not only Shimano. You can get good ride with bosch, Shimano, Yamaha, brose... There are many bikes with constantly been great ride.. They are all the same, just different components ( sram shimano etc) . But you go Shimano because u didnt researched the market well and now you have a problem not me . I wish you good luck with solving that problem..9 cycles and battery has 96%? I would just take my bike back and demand refund.

 

[RickBullotta]

Sadly, the easiest solution for Shimano would be simply to amend their battery life claim, instead of fixing the issue and warrantying thousands or tens of thousands of batteries. Either way, there's clearly a technical issue here...

 

[jimbob]

True. Against which, how many people know about the ST unlocked app and check their battery health? Probably only a small proportion of owners.

I also still have the feeling that its a software issue rather than real degradation, but have no way to prove it. But then, if it was, they must know by now as they'll investigate the returns. And surely they would update the software in new batteries to prevent this?

 

[RickBullotta]

True. Against which, how many people know about the ST unlocked app and check their battery health? Probably only a small proportion of owners.

I also still have the feeling that its a software issue rather than real degradation, but have no way to prove it. But then, if it was, they must know by now as they'll investigate the returns. And surely they would update the software in new batteries to prevent this?

Shimano's Windows eTube software will also show this data FYI. If this was a firmware issue, it would have been fixed by now I'd think - far cheaper than replacing thousands of $500 batteries.

 

[electricbogaloo]

If it would be real degradation then wouldn't the owners notice a rapidly declining range?

 

[RickBullotta]

If it would be real degradation then wouldn't the owners notice a rapidly declining range?

Yes, and I have. Though it's more of a "boiling frog" situation rather then step change degradation.

 

[jimbob]

Shimano's Windows eTube software will also show this data FYI. If this was a firmware issue, it would have been fixed by now I'd think - far cheaper than replacing thousands of $500 batteries.

All good points, although I'd have thought even less people would have the windows software than the app, so still a small sample of users.

The only reason I think it could be real is because, as you say, they'd have fixed it by now.

But, I still fail to believe batteries can be so bad that they loose 10% capacity in 10 cycles. And the fact that all the E8035 batteries in this thread (except 1?) seem to follow the exact same pattern. It just seems too repeatable to be real.

Unfortunately, I think we're all assuming / guessing rather than having any hard facts one way or the other!

 

[Dave_B]

Do we think the new 504 batteries from Shimano will suffer the same issue?

 

[RickBullotta]

All good points, although I'd have thought even less people would have the windows software than the app, so still a small sample of users.

The only reason I think it could be real is because, as you say, they'd have fixed it by now.

But, I still fail to believe batteries can be so bad that they loose 10% capacity in 10 cycles. And the fact that all the E8035 batteries in this thread (except 1?) seem to follow the exact same pattern. It just seems too repeatable to be real.

Unfortunately, I think we're all assuming / guessing rather than having any hard facts one way or the other!

It's also perhaps presumptuous of us to assume it is the batteries, and not the charger(s)...

 

[nosenada]

Yes, and I have. Though it's more of a "boiling frog" situation rather then step change degradation.

I have also noticed a decrease in range. It became very noticeable at 82% health. It also started going from one bar to off instead of having a forced eco reserve period before shutting off.

It's also perhaps presumptuous of us to assume it is the batteries, and not the charger(s)...

I initially thought it may be my e6002 (the slow charger), but Shimano replaced my e6002 charger with an e6000 (fast charger) when it replaced my first set of batteries and I experienced the same rapid degradation in health with the new charger.

Do we think the new 504 batteries from Shimano will suffer the same issue?

It is going to be interesting to see if the new batteries suffer the same rapid decline in health. The old external mounted e8010 batteries do not appear to decline in health like the e8035.

I also still have the feeling that its a software issue rather than real degradation, but have no way to prove it. But then, if it was, they must know by now as they'll investigate the returns. And surely they would update the software in new batteries to prevent this?

I initially thought the same when I started seeing the rapid degradation in battery health, but then I noticed the reduction in range.

My 2 original batteries and my 2 warranty replacement batteries all have a firmware version of "1.0.0.0" as reported in the eTube "E-BIKE Diagnosis Report".

I would not be surprised if there was no way of updating the battery firmware after manufacturing given the safety issues with a BMS.

 

[Milan]

True. Against which, how many people know about the ST unlocked app and check their battery health? Probably only a small proportion of owners.

I also still have the feeling that its a software issue rather than real degradation, but have no way to prove it. But then, if it was, they must know by now as they'll investigate the returns. And surely they would update the software in new batteries to prevent this?

Have you checked the test earlier in this thread? It is clear that it is not a software issue. I have got the ST unlocker and the app does not make up the value, it READS the value. The creator of the app has no control over the readings. It is easier to leave this open for Shimano and act in different countries in a different way, rather than admitting there is a failure and call all owners for replacement as the car producers do

 

[Milan]

I have also noticed a decrease in range. It became very noticeable at 82% health. It also started going from one bar to off instead of having a forced eco reserve period before shutting off.



I initially thought it may be my e6002 (the slow charger), but Shimano replaced my e6002 charger with an e6000 (fast charger) when it replaced my first set of batteries and I experienced the same rapid degradation in health with the new charger.



It is going to be interesting to see if the new batteries suffer the same rapid decline in health. The old external mounted e8010 batteries do not appear to decline in health like the e8035.



I initially thought the same when I started seeing the rapid degradation in battery health, but then I noticed the reduction in range.

My 2 original batteries and my 2 warranty replacement batteries all have a firmware version of "1.0.0.0" as reported in the eTube "E-BIKE Diagnosis Report".

I would not be surprised if there was no way of updating the battery firmware after manufacturing given the safety issues with a BMS.

One of the retailers that I have questioned for the root cause suggested that the issue with the batteries was not the cells themselves but the BMS. They had a bike where they had a similar issue and the customer did not mind losing the warranty. They bypassed or altered the BMS (pardon my non technical info) and figured it was it.

 

[Dave_B]

Someone also commented on Facebook that they run with no BMS connected and they get no E010 errors (having preciously suffered them).
why would that be?

 

[Milan]

If it would be real degradation then wouldn't the owners notice a rapidly declining range?

Do you think 5 km down in ECO range is rapid? I do not find it a lot, but it is 5% down in the battery health and I have only done 1000 km.

 

[jimbob]

Have you checked the test earlier in this thread? It is clear that it is not a software issue. I have got the ST unlocker and the app does not make up the value, it READS the value. The creator of the app has no control over the readings. It is easier to leave this open for Shimano and act in different countries in a different way, rather than admitting there is a failure and call all owners for replacement as the car producers do

I have seen the comparison test in this thread, but wouldn't call it scientific. There is a lot of anecdotal evidence in the thread that the capacity reduction is real, but that doesn't prove it is (or isn't, for that matter). My point is, there is still no conclusive evidence if the degradation is real or a software issue. There are arguments both ways.

I had wanted to try a discharge test over a fixed resistor to prove one way or the other, but it looks like the battery is more complex than I thought and no power is applied to the battery terminals unless a command is given to it. So for now, thats not an option.

With regards to the app readings, I agree it's just reporting the vales from the hardware. When I was referring to potential software issues, I was referring to the battery (BMS) firmware.

I just find it strange that everyone seems to see the exact same degradation characteristics.

 

[jimbob]

Someone also commented on Facebook that they run with no BMS connected and they get no E010 errors (having preciously suffered them).
why would that be?

How do they do that? 3rd party battery?

Seems rather dodgy! BMS' do quite a lot including preventing over voltage of cells and so potential fire etc.

 

[Milan]

I have seen the comparison test in this thread, but wouldn't call it scientific. There is a lot of anecdotal evidence in the thread that the capacity reduction is real, but that doesn't prove it is (or isn't, for that matter). My point is, there is still no conclusive evidence if the degradation is real or a software issue. There are arguments both ways.

I had wanted to try a discharge test over a fixed resistor to prove one way or the other, but it looks like the battery is more complex than I thought and no power is applied to the battery terminals unless a command is given to it. So for now, thats not an option.

With regards to the app readings, I agree it's just reporting the vales from the hardware. When I was referring to potential software issues, I was referring to the battery (BMS) firmware.

I just find it strange that everyone seems to see the exact same degradation characteristics.

Not everyone gets to see the same degradation. Form what I have read so far, the external ones are far better, the worst so far, remains to be the e8035. I agree, we need a tech to provide a fair analysis of the failing e8035. Any tech in this thread who is willing to sacrifice some time and conduct a professional diagnosis with an authorized report on this specific model? Any user who has got a crap battery like this and is close to the tech?

 

[jimbob]

Not everyone gets to see the same degradation. Form what I have read so far, the external ones are far better, the worst so far, remains to be the e8035. I agree, we need a tech to provide a fair analysis of the failing e8035. Any tech in this thread who is willing to sacrifice some time and conduct a professional diagnosis with an authorized report on this specific model? Any user who has got a crap battery like this and is close to the tech?

Sorry, yes, quite right. I was referring just to the E8035 batteries. The external batteries seem to be reporting more realistic values.

 

[electricbogaloo]

Maybe it has to do with the fact that the internal batteries get warmer inside the frame? From what I know they have the same cell type and batteries don't like heat.

Do you think 5 km down in ECO range is rapid? I do not find it a lot, but it is 5% down in the battery health and I have only done 1000 km.

No, because it's hard to say if that's degradation or just the fact that it's hard to measure a system with a human variable involved.

 

[RickBullotta]

This is just horrible. 22 charging cycles and the battery is down to 87% capacity. I'm going to get medieval on Shimano about this one. Second battery that exhibited this behavior.

 

[Milan]

My conclusion here is still the same. I belive the battery cells are ok but Shimano BMS degrades the battery cells down. As longs as your retailer is willing to replace it, and another one, and another one, and another one....and you like the bike you have, you are fine and you should keep doing that hoping that Shimano will notice one day. It seems like it is the nature of some Shimano batteries to degrade so fast.

 

[Spiff]

Looks like Shimano is very conservative to obsolete and replace products with design errors, so it may happen that BMS is faulty and degrades battery. Probably a japanese design manager will have to commit seppuku, but that'll be all, and Shimano will not replace the faulty device.

A good example is the display SC-E8000 with a faulty Bluetooth that is not able to connect to Garmin and many other devices. Shimano released SC-E8000 but it was found soon, that the design is faulty, so following BW display SC-E7000 corrected this problem, but Shimano did not obsolete nor replaced faulty SC-E8000 and 4 years later they are releasing the new color display for EP8, but SC-E8000 is still not obsoleted.

 

[jimbob]

My 8035 battery passed 20 charge cycles the other week and also dropped to 87%. While it's difficult to know if the degradatiin is real or not based on riding, i'm now of the beleif it's real and not just a software glitch.

I'm planning to wait for a few more cycles before returning it to maximise my chance of succes of a return. And also, from whats being seen on here, the replacement will just do the same anyway!

 

[guika]

Same here.... 10 cycle and than 90%. 520km 2month
The difference here is , that I have slow charger and I stored my bike 100% after charge. 2-3 ride per week
I always charged up after a ride.
I had 50-50 mixed 100-0% discharge and 100-50 than back 100 charge.
I did not used much boost.

IMO it must be something different, because some of us have faster charger, some of us charge before ride usage . but same outcome.

What I have got here, is that yesterday I have read out my bike data. It was 9 cycle and 100% today I made a ride and charged and it showed the 10 cycle 90%. This pattern we all have.

That can not be coincident , and that show a software issue to me, but maybe I am wrong.

I have added my details, and you can see that my bike power settings are lowered too.

Hope that helps.

 

[electricbogaloo]

Storing it constantly at 100% is the second unhealthiest state after leaving it sit at 0% meaning it is the second fastest way to cell degradation.

Did your battery health drop rapidly from 100% to 90 or gradually?

Mine is approaching 40 cycles I think and degraded to 98%. I store it between 30 and 70%.

If I need to charge it to 100% I do it right before the ride so I had it sit around fully charged for maybe 2-3 days when I was traveling to a destination without electricity by car.

Also when I empty it completely (which is really rare) I charge it up immediately.

 

[jimbob]

Storing it constantly at 100% is the second unhealthiest state after leaving it sit at 0% meaning it is the second fastest way to cell degradation.

Did your battery health drop rapidly from 100% to 90 or gradually?

Mine is approaching 40 cycles I think and degraded to 98%. I store it between 30 and 70%.

If I need to charge it to 100% I do it right before the ride so I had it sit around fully charged for maybe 2-3 days when I was traveling to a destination without electricity by car.

Also when I empty it completely (which is really rare) I charge it up immediately.

Which battery do you have? The issues seen seem to be limited to the 8035 internal battery.