Shimano BT-E8035 Integrated Battery Issue: very fast degrading and loss of range

Milan

Member
Sep 9, 2020
91
34
Czech Republic
From what I have read and gathered it looks quite clear that BT-E8035 is poorly designed. You can try hard and do the best you can (store it well, charge it well, drain it reasonably), yet you will end up having the worst bike battery that is degrading fast and will steal your km range. Most occasional users will not notice but frequent users, like myself, will see the fast degrading in capacity and loss of range. Please do not respond to this thread with your suggestions how we should treat this specific model/type of battery. You will not help this thread unless you have this battery and are using it frequently. I am just sadly trying to inform all owners of BT-E8035 that we all have the same problem and the way out is to gather evidence/stats and provide this information to Shimano to resolve this. My point here is clear: this battery is faulty, poorly designed and is not fit for purpose. Anyone who has got a bike with this battery should know about it and should get in touch with Shimano to make their claim. The sooner, the better. Could you, dear owners of BT-E8035, provide simple stats + commenting how you actually use the bike (such as I ride every other day, charge it this or another way, what modes you use, what temperatures you bike, where you store your bike while charging). From what we know, this battery in 10 cycles losses 10% percent of capacity. After that the degrading slows down a little but it simply continues and after around 5000 km, your battery has got 76% of capacity and is dead and not fit for purpose. Use the template below to provide evidence that this really true. The template for any further posts is this:

My battery stats:

1) # of charging cycles = 92

2) remaining capacity = 76%

3) charger = EC-E6002

4) km total = 4989

5) assistance = most rides 97% eco mode, 1-2% trail, boost almost never, off mode employed downhill

6) charging style and storage = bike stored inhouse at 22 degrees, charged prior to biking next day at the temp of 22 degrees, if not biking next day left at what is left (two to three bars). If not biking longer than two days, charged to approx. 80% and left to be fully charged prior to any future rides. Temperatures outside here are 15 to 35 spring to summer. -5 to 5 during fall and winter. The drop in range was fast in the first six months, i.e. lost 16% of the battery capacity per 1500 km. Most users experience 10% loss of capacity and range in the first ten cycles.

In order to provide stats, unless you own Shimano diagnostic tool, you will most likely have to download STunlocker app and connect it to your bike. You may think about this app whatever you want to, nonetheless, it gets us where we need to. It reads the data that Shimano dumps for their diagnostic tool. Spare us of your posts and discussions about the use of STunlocker. The app is great and perfect help for our cause.
 

Gary

Old Tartan Bollocks
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mine -
2yrs old.
5000miles+ (ridden around 8-12 times a week, but not every day)
161 charge cycles
84% health
I use all assistance modes and have ridden a few E8000 motors tro destruction/warranty replacement with this battery
I have 3 chargers 2x EC-6000, 1x EC-6002 (1 at work, 1 at home, 1 at my partner's house
Bike is always stored indoors (but not at any specific temp) I don't bother doing anything special when charging the bike and generally top it right up to full every time.

Shimano guarantee them for 2 years from purchase. And to be at 60% health or above after 1000 cycles (which is pretty much impossible in 2 years)

Good luck even finding a replacement at all right now nevermind a warranty replacement.

From what we know, this battery in 10 cycles losses 10% percent of capacity. After that the degrading slows down a little but it simply continues and after around 5000 km, your battery has got 76% of capacity and is dead and not fit for purpose
If you're getting all your information from the Stunlocker app. I wouldn't be too sure the battery health level data you're seeing is actually accurate
I had 2 shimano bikes for a short while and the app read around 10% difference in health for the SAME battery depending on which bike it was fitted to.

Basically you're wasting your time.
 

Milan

Member
Sep 9, 2020
91
34
Czech Republic
mine -
2yrs old.
5000miles+ (ridden around 8-12 times a week, but not every day)
161 charge cycles
84% health
I use all assistance modes and have ridden a few E8000 motors tro destruction/warranty replacement with this battery
I have 3 chargers 2x EC-6000, 1x EC-6002 (1 at work, 1 at home, 1 at my partner's house
Bike is always stored indoors (but not at any specific temp) I don't bother doing anything special when charging the bike and generally top it right up to full every time.

Shimano guarantee them for 2 years from purchase. And to be at 60% health or above after 1000 cycles (which is pretty much impossible in 2 years)

Good luck even finding a replacement at all right now nevermind a warranty replacement.


If you're getting all your information from the Stunlocker app. I wouldn't be too sure the battery health level data you're seeing is actually accurate
I had 2 shimano bikes for a short while and the app read around 10% difference in health for the SAME battery depending on which bike it was fitted to.

Basically you're wasting your time.
Thanks a lot for your response. STunlocker vs. Shimano diagnostic tool, health is always the same figure. You take your bike to Shimano and ask them to tell you the capacity of the battery, the figure they will tell you, is the figure you will see in the STunlocker app. No big deal, not much to discuss. I hope I am not wasting my time gathering this info, in the end you may benefit from this, for now I can only tell you that you seem to be the kind of the luckier one with your battery :cool:
 

chtabajara

New Member
Feb 16, 2021
13
6
Brazil
My battery stats:

1) # of charging cycles = 11

2) remaining capacity = 90%

3) charger = EC-E6002

4) km total = 511

5) assistance = most rides 50% eco mode, 47% trail, 3% boost

6) charging style and storage = bike stored inhouse at 30 degrees(brazil), charged after ride sometimes and prior ride sometimes.but with it's rainy sometimes leaved charged for 3, 4, 5 days. Never Leaved empty
 

Milan

Member
Sep 9, 2020
91
34
Czech Republic
Please re-read what I wrote about Stunlocker's battery heath reading.
The same motors? Same mode of riding? Same ways of charging? Lots of variables, I do admit, nontheless, what I was trying to say, is that with the Shimano diagnostic tool, the readings would be the same. The system dumps the readings and it has nothing to do with what app you display that: be it Shimano Etube or STunlocker. I got both and they show the same readings. To put it bluntly: forget about the app, the health remains the heatlth and this figure is the same whatever the app you choose. Why the app shows different readings with the same battery and a different bike has a lot to do with different settings of a particular bike and it is not the point of this thread, I am sorry to say....This thread and the users of the battery E8035 should know that the battery or its firmware is faulty and that Shimano has to take action. If you happy with your batteries, no worries, enjoy your rides and thanks for your stats of a happy user.
 

Gary

Old Tartan Bollocks
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The same motors? Same mode of riding? Same ways of charging? Lots of variables
None of which should matter at all if you are simply reading the battery health figure of the same battery fitted to multiple bikes back to back.
Why the app shows different readings with the same battery and a different bike has a lot to do with different settings of a particular bike
OMG
now it's my turn to put it bluntly:
Please now re-read what YOU just typed above until you realise you're actually agreeing that Stunlocker infact did not consistently read the same BATTERY health value of the same battery. So which value is to be believed?

This thread and the users of the battery E8035 should know that the battery or its firmware is faulty and that Shimano has to take action.
That's an incredibly bold statement. Care to back up your claim with some actual evidence?
So far all I've read is your disatisfaction of a 76% battery health reading from a personal case study of ONE with absolutely zero evidence of a common fault with this particular battery model.
If your battery is indeed faulty, That's what your warranty is for. so use it.. I'm not saying faults can't or don't happen.
 

Milan

Member
Sep 9, 2020
91
34
Czech Republic
None of which should matter at all if you are simply reading the battery health figure of the same battery fitted to multiple bikes back to back.
OMG
now it's my turn to put it bluntly:
Please now re-read what YOU just typed above until you realise you're actually agreeing that Stunlocker infact did not consistently read the same BATTERY health value of the same battery. So which value is to be believed?


That's an incredibly bold statement. Care to back up your claim with some actual evidence?
So far all I've read is your disatisfaction of a 76% battery health reading from a personal case study of ONE with absolutely zero evidence of a common fault with this particular battery model.
If your battery is indeed faulty, That's what your warranty is for. so use it.. I'm not saying faults can't or don't happen.
Hi Gary, sorry for being too abrupt with my statements. I have re-read your posts 6 or 7 times and sort of still loose your point. Are you trying to help this cause or you are just one of those guys who know better than the others? In this thread, I do not want to discuss STunlocker, clear or not? If your readings of the same battery are 10% different with your two different bikes, my guess is that it has something to do with the circuit/temperature when you turn the bike on. I assume that the Shimano system, both firmware and hardware, is checked against and dumps some readings. It is no wonder that with some voltage and temperature the response to the system may be 10% different. Are your readings of your two bikes 10% different in both Shimano diagnostic tool and STunlocker? I have two bikes Ghost and Merida and I cannot swap batteries, however, if I check ‘battery health’ with STunlocker or Shimano, it provides the same readings for both of my bikes. If you are questioning STunlocker or Shimano diagnostic tool, go ahead and start up your own thread, I am sorry but I find your point in this regards misleading and inappropriate in this thread. As regards the warranty of mine. I am actively using it and it has been over three weeks now that I have been waiting for Shimano to replace my battery. Why? Because the evidence is quite clear in the post here. Sure, I am dissatisfied and unhappy and would like to have a battery that is more in line with what the industry standard is. I do not want to have the battery replaced over and over every 12 months. E8035 has got an issue to resolve and this is why this thread originated. Do not post responses that relativize STunlocker, provide suggestions for proper care, and tell me I am wasting my time. I am wasting it as I am fully convinced this battery is faulty right from the scratch.
 

R120

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Personally I dont trust the data from any of the apps - on my external batteries which are respectively nearly 3 years old and 2 and a half years old, I don't see that much difference to when they where range wise new in the real world.

Part of the problem I think is that with motor and software updates how the battery gets drained must change, meaning that someone running an older software version might be getting different results.

What I do see is that over the winter due to the conditions and I presume temperature the range drops off.

I also think whetter the bike is running EU limits, US Limit, or derestricted makes quite a difference. - I think for the info you want you need this to be stated.

One of my bikes is set to EU limit, other to US, and like for like the US limit one will go through the battery noticeably quicker than the EU limit one because it is using the motor assistance more of the time.
 

Milan

Member
Sep 9, 2020
91
34
Czech Republic
I think that might have been a bug with STUNLOCKER and e7000 motors in how the battery data is interpreted.
It looks like Zimm knows Gary and Gary knows Zimm. Sorry, for making it difficult. Each of your bikes have got a number of firmwares. These firmwares have certain types of circuits which have a number of variables depending on the temeprature and I am sorry to say (previously)"employed settings. STunlocker and Shimano diagnostic tool "read" what is easily available. Mostly they do not read any bugs. They read what the Shimano system offers (motor, battery, screen,..) STunlocker and Shimano diagnostic tool does not evaluate and this is important, these apps do not EVALUATE/INTERPRETE, they simply READ the stats. You press the button, they input the current available volatage, launch some short procedure and dump the characteristics. There is no bug regarding E7000 and STunlocker. Forget about it, STunlocker does not interfere with what is dumped. What dumps the chars, is the the Simano system. You are totally wrong.....
 

Milan

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Sep 9, 2020
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34
Czech Republic
Personally I dont trust the data from any of the apps - on my external batteries which are respectively nearly 3 years old and 2 and a half years old, I don't see that much difference to when they where range wise new in the real world.

Part of the problem I think is that with motor and software updates how the battery gets drained must change, meaning that someone running an older software version might be getting different results.

What I do see is that over the winter due to the conditions and I presume temperature the range drops off.

I also think whetter the bike is running EU limits, US Limit, or derestricted makes quite a difference. - I think for the info you want you need this to be stated.

One of my bikes is set to EU limit, other to US, and like for like the US limit one will go through the battery noticeably quicker than the EU limit one because it is using the motor assistance more of the time.
ECO mode, after you have charged your battery, tells you more or less what capacity your battery is. If my capcity is 76%, your ECO mode will show you 77 km range. If you have a new bike, or better still, you have a brand new bike, your ECO mode will show you 99 or 100 km. It does not matter what mode you are using, TRAIL, US mode, EU mode, you simply waste the capacity of your battery. It is very easy to loose all your 100 km range or 77 range if you decide to go up a very steep hill. It may take 10 to 20 mins to waste it and drain the whole battery. The point here is that you do not get tha far if you have an E8035 as compared to other batteries. Use the same set up with an external battery, ride a stronger 8000 Shimano motor vs. 7000 and the same E8035 battery and you will just end up to be the last one. This E8035 battery is not designed and manufactured appropriate and hence requires a redesign.
 

Zimmerframe

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Sorry, for making it difficult.
Dearest @Milan , there is no need to apologise.

You are correct on one point though, I have seen @Gary previously here on the forum. He has also stalked me in the hope that I'm an attractive intelligent female (he's wrong on all accounts).

You are also correct that the Shimano system stores various items of information. In Hex. I've tried to decode the old Shimano"Blackbox" previously but gave up and went for a ride instead following some sound advice.

Stunlocker takes these variables and converts them into decimal so they're easy for people to read.

However, the e7000 uses a different numbering range in how it outputs the battery health. Stunlocker didn't take this into account, so even with new batteries, it would show the health at 90% on e7000 bikes as it decoded the shimano data incorrectly.

....

As for all your other bits, I think they must get lost in translation. Personally, I found with the BT-E8035 I had more range than with other comparatively sized batteries.

If I'm reading correctly, you're suggesting that there is the equivalent of a magic hole and when you ride up hill - the charge will leak out in only 10 or 20 minutes ? Or it uses the angle sensor in the motor to work out you're climbing and diverts 90% of the battery energy to run the saddle air conditioner ?

It is true though. Trail mode (can) and Boost mode (will) use the battery faster. They provide more relative assistance and more power from the motor.

Strangely, if you ride up things, this uses more energy than riding on flat things. We might have to discuss this part in the conspiracy theory thread so we don't get too distracted here.

You can test this theory without an e-bike. Park your car on the flat and try to push it - it's hard, but you can do it. Park your car on a hill and try to push the car up the hill - it's a lot harder - it requires more power and more energy ! (Warning ! don't try this alone or you might run yourself over with your car. Or take off the brake, exit the car and watch your car roll away down the hill)

Try the same test with a wheel barrow and it's a lot easier. This is where another factor comes into play. If something is heavier, it requires more energy to move it. It requires proportionally, even more energy to lift it as you fight the effects of Gravity. The wheel barrow test is much safer to perform alone and can also be done with a full wheel barrow and an empty wheelbarrow.

In conclusion. You are probably just a big guy ? 2M ? 120+kg - so you will use a lot more power from your battery in Trail and Boost where there are no limits - it will use as much power as it can. Unlike Eco, where there is a limit on how much power it can use.

What you could do to obtain more range is to use stunlocker to reduce the overall maximum power of the motor, reduce the power and torque limits and make it more like an EP8. This should increase your range, even when climbing in trail and boost.
 

nosenada

Member
Nov 26, 2019
50
29
California
I have owned four e8035 batteries. All 4 batteries rapidly decline in health as follows. So frustrating that Shimano will not fix the issue or warranty my batteries again. I would buy a new ep800 with a e8036 battery, but I am worried the e8036 or any other Shimano system will have the same issues (and major delays getting warranty parts).

Questions 1-2:

Battery 1 - Original Battery (purchased 10/1/2019)
90% health; 10 cycles
87% heath; 23 cycles (at 87% Shimano agreed to warranty)
85% health; 32 cycles
84% health; 38 cycles
82% health; 40 cycles

Battery 2 - New Battery Purchased from LBS (purchased 11/13/2019)
90% health; 10 cycles
87% health; 20 cycles (either at 90% or 87% Shimano agreed to warranty)
85% health; 30 cycles

Battery 3 - Warranty Batt (24) (warranty replacement 4/23/2020) (charged to 100% after each ride, stored/charged indoors)
91% health; 4 cycles and - only 20 days old (4/23/2020) (Shimano said they wanted more degradation)
89% health; 11 cycles
87% health; 20 cycles (Shimano refused warranty says has to be 60% 10/6/2020)
84% health; 30 cycles (11/29/2020)
82% health; 40 cycles (1/8/2021)
83% health; 42 cycles (1/20/2021) (ran to empty so likely recalibrated)
82% health; 48 cycles (2/6/2021)
80% health; 50 cycles (2/13/2021)

Battery 4 - Warranty Batt (B0) (warranty replacement 4/23/2020) (charged to 40-70% after each ride, stored/charged indoors)
90% health; 11 cycles (Shimano said they wanted more degradation)
90% health; 14 cycles
87% health; 21 cycles (Shimano refused warranty says has to be 60% 10/6/2020)
85% health; 30 cycles (12/20/2020)
82% health; 37 cycles (2/15/2021) (ran to empty so may have recalibrated)

Question 3: charger = EC-E6002 (for battery 1 and 2); EC-E6000 (3 different e6000 chargers for batteries 1-4)

Question 4: total distance = 5,472km (3,400miles)

Question 5: assistance = mostly trail and boost, rarely eco (except 2 months I waited for a warranty replacement motor)

Question 6: Charged and stored indoors. Batteries 1, 2, and 4 stored at 40-70% SoC, Battery 3 charged to 100% SoC after a ride.
 

Milan

Member
Sep 9, 2020
91
34
Czech Republic
I have owned four e8035 batteries. All 4 batteries rapidly decline in health as follows. So frustrating that Shimano will not fix the issue or warranty my batteries again. I would buy a new ep800 with a e8036 battery, but I am worried the e8036 or any other Shimano system will have the same issues (and major delays getting warranty parts).

Questions 1-2:

Battery 1 - Original Battery (purchased 10/1/2019)
90% health; 10 cycles
87% heath; 23 cycles (at 87% Shimano agreed to warranty)
85% health; 32 cycles
84% health; 38 cycles
82% health; 40 cycles

Battery 2 - New Battery Purchased from LBS (purchased 11/13/2019)
90% health; 10 cycles
87% health; 20 cycles (either at 90% or 87% Shimano agreed to warranty)
85% health; 30 cycles

Battery 3 - Warranty Batt (24) (warranty replacement 4/23/2020) (charged to 100% after each ride, stored/charged indoors)
91% health; 4 cycles and - only 20 days old (4/23/2020) (Shimano said they wanted more degradation)
89% health; 11 cycles
87% health; 20 cycles (Shimano refused warranty says has to be 60% 10/6/2020)
84% health; 30 cycles (11/29/2020)
82% health; 40 cycles (1/8/2021)
83% health; 42 cycles (1/20/2021) (ran to empty so likely recalibrated)
82% health; 48 cycles (2/6/2021)
80% health; 50 cycles (2/13/2021)

Battery 4 - Warranty Batt (B0) (warranty replacement 4/23/2020) (charged to 40-70% after each ride, stored/charged indoors)
90% health; 11 cycles (Shimano said they wanted more degradation)
90% health; 14 cycles
87% health; 21 cycles (Shimano refused warranty says has to be 60% 10/6/2020)
85% health; 30 cycles (12/20/2020)
82% health; 37 cycles (2/15/2021) (ran to empty so may have recalibrated)

Question 3: charger = EC-E6002 (for battery 1 and 2); EC-E6000 (3 different e6000 chargers for batteries 1-4)

Question 4: total distance = 5,472km (3,400miles)

Question 5: assistance = mostly trail and boost, rarely eco (except 2 months I waited for a warranty replacement motor)

Question 6: Charged and stored indoors. Batteries 1, 2, and 4 stored at 40-70% SoC, Battery 3 charged to 100% SoC after a ride.
Hey, thanks a lot, gorgeous, I thought I would just end up going on with those....you know who. You have just nailed it with your stats and I myself, I do not want to go through the same process like you have done. In a naive way, like Mr. Toyota does from time to time, I want Mr. Shimano to appologise to you and fix that crap with the next battery.
 

Milan

Member
Sep 9, 2020
91
34
Czech Republic
Dearest @Milan , there is no need to apologise.

You are correct on one point though, I have seen @Gary previously here on the forum. He has also stalked me in the hope that I'm an attractive intelligent female (he's wrong on all accounts).

You are also correct that the Shimano system stores various items of information. In Hex. I've tried to decode the old Shimano"Blackbox" previously but gave up and went for a ride instead following some sound advice.

Stunlocker takes these variables and converts them into decimal so they're easy for people to read.

However, the e7000 uses a different numbering range in how it outputs the battery health. Stunlocker didn't take this into account, so even with new batteries, it would show the health at 90% on e7000 bikes as it decoded the shimano data incorrectly.

....

As for all your other bits, I think they must get lost in translation. Personally, I found with the BT-E8035 I had more range than with other comparatively sized batteries.

If I'm reading correctly, you're suggesting that there is the equivalent of a magic hole and when you ride up hill - the charge will leak out in only 10 or 20 minutes ? Or it uses the angle sensor in the motor to work out you're climbing and diverts 90% of the battery energy to run the saddle air conditioner ?

It is true though. Trail mode (can) and Boost mode (will) use the battery faster. They provide more relative assistance and more power from the motor.

Strangely, if you ride up things, this uses more energy than riding on flat things. We might have to discuss this part in the conspiracy theory thread so we don't get too distracted here.

You can test this theory without an e-bike. Park your car on the flat and try to push it - it's hard, but you can do it. Park your car on a hill and try to push the car up the hill - it's a lot harder - it requires more power and more energy ! (Warning ! don't try this alone or you might run yourself over with your car. Or take off the brake, exit the car and watch your car roll away down the hill)

Try the same test with a wheel barrow and it's a lot easier. This is where another factor comes into play. If something is heavier, it requires more energy to move it. It requires proportionally, even more energy to lift it as you fight the effects of Gravity. The wheel barrow test is much safer to perform alone and can also be done with a full wheel barrow and an empty wheelbarrow.

In conclusion. You are probably just a big guy ? 2M ? 120+kg - so you will use a lot more power from your battery in Trail and Boost where there are no limits - it will use as much power as it can. Unlike Eco, where there is a limit on how much power it can use.

What you could do to obtain more range is to use stunlocker to reduce the overall maximum power of the motor, reduce the power and torque limits and make it more like an EP8. This should increase your range, even when climbing in trail and boost.

Hi Zimmy, and thanks a lot for your post. It feels great that Gary is still uncertain about your gender. Never thought you would be a female. I will make it very easy for him. I am 100% male, love long dark haired females and ebiking. Gary and Zimmy, however, are making this thread a piece of.....You know what, I just want stats and you fill it with loads of s….. Send me a link where the two of you will start to be academic about a BT-E8035 and I will join this rightaway. We can talk about anything: bugs, ups and downs, weights, and we will forget about the fact that we need stats. Look, I am 89 kg, 183.5 cm and I started ebiking this battery in November 2020. When I did, I was 99 kg, same size :) the battery health was 84% to 85%. Now, it is 76% while I lost 10 kg. I do not care whether the data is interpreted somehow by any app, but coincidentally, Shimano app and STunlocker app read the health the same: 76%. This battery of mine is a piece of crap. Yours, or Gary’s could be a lot better but Shimano and me myself would like to know why. Local Shimano reps have no clue why my battery is dead. All they can do is to wait until they get a response from Germany or Japan. Please, if I may ask, anybody who wants to post in this thread, just fill the template. Cut the c… If you cannot resist and want to be academic, send it to me personally, do not post it here. I know that a lot could have been lost in translation since English is not my mother tongue, but I will conclude here once and again, this battery is a crap, faulty and we only need substantial evidence to make the claim with Shimano.
 

R120

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Have your noticed an actual real world degradation in range in line with the data?

Interested as I don’t trust the reading from either the official or 3rd party apps, only the real world range.
 

Milan

Member
Sep 9, 2020
91
34
Czech Republic
Have your noticed an actual real world degradation in range in line with the data?

Interested as I don’t trust the reading from either the official or 3rd party apps, only the real world range.
Sure, the BT-E8035s degrade real world, the battery health in this case is not an illusion. A wrong figure as you suggest, poorly read or dumped by the system, forget about it, it is real. We all know tha ECO range after fully charged is a fairy tale. I do not know what to say what the ECO range is when your battery health goes down to 76%. Comedy or tragedy? I am happy if can make 30 to 35 km.
 

Gary

Old Tartan Bollocks
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Send me a link where the two of you will start to be academic about a BT-E8035 and I will join this rightaway. We can talk about anything: bugs, ups and downs, weights
I'm not disputing Li ion batteries degrade over time. They all do. And it's something we all have to accept.
I'd just have liked you to have had a glimmer of actual hard evidence that this is an actual issue across all E8035s rather than just a repetitive tirade of "this is crap".
I agree with our resident longhaired brunette R120 that battery health is nowhere near as cut and dried as you seem to be making out and for you to be losing battery health so rapidly there may well be as yet undisclosed external reasons compounding your quicker battery degradation. Your chosen list of 6 questions is really not enough data to determine the route of any similar issues you may discover. and as Shimano have already covered their backs by warrantying their batteries for upto 2 years and 60%+ health it's unlikely to get you anywhere other than even more wound up.
 

Milan

Member
Sep 9, 2020
91
34
Czech Republic
I'm not disputing Li ion batteries degrade over time. They all do. And it's something we all have to accept.
I'd just have liked you to have had a glimmer of actual hard evidence that this is an actual issue across all E8035s rather than just a repetitive tirade of "this is crap".
I agree with our resident longhaired brunette R120 that battery health is nowhere near as cut and dried as you seem to be making out and for you to be losing battery health so rapidly there may well be as yet undisclosed external reasons compounding your quicker battery degradation. Your chosen list of 6 questions is really not enough data to determine the route of any similar issues you may discover. and as Shimano have already covered their backs by warrantying their batteries for upto 2 years and 60%+ health it's unlikely to get you anywhere other than even more wound up.
OK, fine, please refine my list then, thanks a lot in advance. What other evidence do you think we would need to claim that BT-E8035 is faulty, poorly designed, not industry standard?
 

Gary

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You don't seem to realise that you haven't actually found any physical evidence for any of those claims at all.

They're kind of big claims to be making
 

Milan

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Sep 9, 2020
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You don't seem to realise that you haven't actually found any physical evidence for any of those claims at all.

They're kind of big claims to be making
What physical evidence would you please suggest? Perhaps I am able to provide it....
 

Gary

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If you were suitably knowledgeable enough concerning battery architecture you wouldn't have to ask.
 

Gary

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10,702
the internet
Correct me if I am wrong but I don't think you've contributed to the forum on any other subject? And so far you've proven yourself to be the type of guy to jump straight to conclusions and make a screaming drama wildly claiming injustice, negligence and fault with a product you seemingly have very little understanding of whilst having almost no substantiated evidence to back up your claims. Not to mention your aparent lack of even a vague understanding of the product's design remit and blatant disregard for the manufacturers acceptible projected operating lifespan as stated by it's warranty. I suggest you take some time to do some research and learning to aquaint yourself with what you are talking about before trying to gather pointless information or talk about sending a lawyer to uphold your unsubstantiated claims against a multi billion $ corporation's products. Especially when you have not actually even experienced a failure of the product in question.

There are forum members here with far greater understanding and knowledge of battery architecture than I. Maybe one of them has enough patience and kindness to take the time to explain the science to you in depth.
 

Milan

Member
Sep 9, 2020
91
34
Czech Republic
Correct me if I am wrong but I don't think you've contributed to the forum on any other subject? And so far you've proven yourself to be the type of guy to jump straight to conclusions and make a screaming drama wildly claiming injustice, negligence and fault with a product you seemingly have very little understanding of whilst having almost no substantiated evidence to back up your claims. Not to mention your aparent lack of even a vague understanding of the product's design remit and blatant disregard for the manufacturers acceptible projected operating lifespan as stated by it's warranty. I suggest you take some time to do some research and learning to aquaint yourself with what you are talking about before trying to gather pointless information or talk about sending a lawyer to uphold your unsubstantiated claims against a multi billion $ corporation's products. Especially when you have not actually even experienced a failure of the product in question.

There are forum members here with far greater understanding and knowledge of battery architecture than I. Maybe one of them has enough patience and kindness to take the time to explain the science to you in depth.
The information or some form of stats that I am trying to compile and you consider pointless is based on what I was asked by a number of ebike retailers, ebikers and after all Shimano too when inquiring why this battery could be degrading so fast. I have got no problem saying: please could somebody who is knowledgeable, kind and patient enough update me on the missing parts of this puzzle that Gary is pointing out? I’ll be happy if you send me a link or two to understand why there are, so far, 6 the same batteries in this thread with the same fast degrading profile. Never thought you have to contribute to ask for information. If this is the forum’s policy then fair enough.
 

chtabajara

New Member
Feb 16, 2021
13
6
Brazil
Just to feed more information. Talking to friends who have the same battery with more or less the same number of cycles. I decided to cross information and without any surprise all of them presenting the same pattern, which in my opinion, seems to be a flaw in the firmware of these batteries.

All 3 with 90% health in any application.

and anothe friend ha a battery with 9 cycles with 100% health.

Seeing all these facts, it seems that the drop in the number happens every 10 cycles.
In the past users of the firsts speshhh Turbo Levo reported a similar problem, which was corrected through a firmware update, perhaps this is the case.
 

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