Shimano Battery Life Poll

Husky430

E*POWAH Master
Jul 8, 2019
584
988
Glasshouse Mts - Australia
Just about to clock over 3000km and battery was doing well but just dropped about 6% at once from 96 to 90%.
I'm running the external 500 amp hour battery by the way.
Don't know why such a big drop at once as haven't done anything different to normal. Was thinking myself I'm pretty lucky to have nearly 50 cycles and only have dropped 4% battery health, then hitting 50 charge cycles and the big drop, don't know if that just a coincidence or not. Still can do a fair ride on it and in hilly country on the weekend it had done around 18km before the first bar dropped on the display.
 

Blokie

Member
May 30, 2019
71
44
Derbyshire, UK
Is there any feedback on the performance of the E8036 batteries? (the 630Wh internal ones used for the EP8). Really hoping that it doesn;t suffer the same issues that the 8035 has...
 

Pivot

E*POWAH Master
Jun 11, 2020
668
1,088
New Forest, England
My Shimano E8010 dropped from 100% to 90% (battery health) after circa 500km and 10 cycles (the count was clearly incorrect)

I have done now 1’500km and still on the 90% level (showing 20 cycles?!)

If the charging cycles are counted incorrectly, how do we know that battery health is any better?

My NBS tells me that it is perfectly normal behaviour and I shouldn’t stress.
 

guika

Member
Oct 31, 2020
33
11
HU
My Shimano E8010 dropped from 100% to 90% (battery health) after circa 500km and 10 cycles (the count was clearly incorrect)

I have done now 1’500km and still on the 90% level (showing 20 cycles?!)

If the charging cycles are counted incorrectly, how do we know that battery health is any better?

My NBS tells me that it is perfectly normal behaviour and I shouldn’t stress.
Must be something strange here. Mine dropped 90% on the 10th cycle and now on the 20th 87% as everybody else here. Looks like these drops are built in regardless how we use how we charge. I am sure something is not right with Shimano batts. Mine is 8035 504wh
 

Pivot

E*POWAH Master
Jun 11, 2020
668
1,088
New Forest, England
Must be something strange here. Mine dropped 90% on the 10th cycle and now on the 20th 87% as everybody else here. Looks like these drops are built in regardless how we use how we charge. I am sure something is not right with Shimano batts. Mine is 8035 504wh

Ditto.
My battery just ticked over to 20 cycles(?) at +1’500km(?) and shows 87% battery health(?), very conspicuous!
 

Growmac

Well-known member
Subscriber
Dec 4, 2020
375
391
Wilts, UK
My Shimano E8010 dropped from 100% to 90% (battery health) after circa 500km and 10 cycles (the count was clearly incorrect)

Just to check. Charge cycles are counted as multiples of 100% charge used, not number of times charged. So ten rides where you use 50% of the battery would be 5 charge cycles.

10 cycles for 500 km sounds quite good, assuming you're on hilly off road. I'd probably only get 400 km.
 

guika

Member
Oct 31, 2020
33
11
HU
Just to check. Charge cycles are counted as multiples of 100% charge used, not number of times charged. So ten rides where you use 50% of the battery would be 5 charge cycles.

10 cycles for 500 km sounds quite good, assuming you're on hilly off road. I'd probably only get 400 km.
That is correct. A cycle counts for 504wh charge which can come from multiple charges. Yes in avg I do hilly trips only. With avg 500m-600m climbs.
 

Pivot

E*POWAH Master
Jun 11, 2020
668
1,088
New Forest, England
Just to check. Charge cycles are counted as multiples of 100% charge used, not number of times charged. So ten rides where you use 50% of the battery would be 5 charge cycles.

10 cycles for 500 km sounds quite good, assuming you're on hilly off road. I'd probably only get 400 km.

Very good point GM!

We need to understand the Shimano logic and equally important what is the optimal use of this technology.

From the logic perspective, Shimano states that we should have 60% capacity left after 1000 cycles. That doesn’t add-up in my Kopf, when I had 90% at 10 cycles and now 87% at 20.

I understand that Lithium-Ion based batteries don’t like to be left discharged, but also don’t like being left continuously on a charger. I charge my bike after every ride and I store it charged for when I get a cabin-fever and I need to clear the cobwebs in my head.

Tesla has probably the most advanced battery management capability. Apple is pretty good as well. Shimano might be equally good, but sadly it is not as well published.
 

guika

Member
Oct 31, 2020
33
11
HU
Very good point GM!

We need to understand the Shimano logic and equally important what is the optimal use of this technology.

From the logic perspective, Shimano states that we should have 60% capacity left after 1000 cycles. That doesn’t add-up in my Kopf, when I had 90% at 10 cycles and now 87% at 20.

I understand that Lithium-Ion based batteries don’t like to be left discharged, but also don’t like being left continuously on a charger. I charge my bike after every ride and I store it charged for when I get a cabin-fever and I need to clear the cobwebs in my head.

Tesla has probably the most advanced battery management capability. Apple is pretty good as well. Shimano might be equally good, but sadly it is not as well published.
The strange story here is that only on battery type 8035 we all have the same degradation. 90 than 87. It is far away on that hiw we use charge and store. Even lets say shim uses crap cells what i dont think, but lets assume. than we all would see bigger degradation than other batteries but our values would differ from each other. Like after 10 we would have 93;91;89;99 etc and not exact 90 and the worst part shows after 20 cycles than we all have 87%

For sure it is software issue! Otherwisethe values would not match !
 

OleP

Member
Dec 3, 2020
16
7
Roskilde, Denmark
The strange story here is that only on battery type 8035 we all have the same degradation
No, it also happen with my BT-E6001 (500Wh rack mount) and E6100 motor never used for steep hills. Most flat roads and normal assistance (city bike).
90 % health @ 10 charge cycles
87 % health @ 20 charge cycles . Bike now at 2200 km and 26 Cycles.
I'm unsure if it is a software bug. The input Wh per full charge has not changed significantly since the battery was 100 % healthy.
It's a very controversial issue - In a German Forum there are now over 2810 posts (and counting) about the very same issue. That tread started 3½ years ago!
 
Last edited:

guika

Member
Oct 31, 2020
33
11
HU
No, it also happen with my BT-E6001 (500Wh rack mount) and E6100 motor never used for steep hills. Most flat roads and normal assistance (city bike).
90 % health @ 10 charge cycles
87 % health @ 20 charge cycles . Bike now at 2200 km and 26 Cycles.
I'm unsure if it is a software bug. The input Wh per full charge has not changed significantly since the battery was 100 % healthy.
It's a very controversial issue - In a German Forum there are now over 2810 posts (and counting) about the very same issue. That tread started 3½ years ago!
Well that is anyhow very strange that your values are matching with mine... :/
 

OleP

Member
Dec 3, 2020
16
7
Roskilde, Denmark
Well that is anyhow very strange that your values are matching with mine... :/
Yes and No, because IF the health (capacity) reading is degrading rapidly, it always does it that way (90/10, 87/20...) but some people state that they have charged their battery, say 30+ full cycles and see e.g. 99 - 98 % health.
 

guika

Member
Oct 31, 2020
33
11
HU
Yes and No, because IF the health (capacity) reading is degrading rapidly, it always does it that way (90/10, 87/20...) but some people state that they have charged their battery, say 30+ full cycles and see e.g. 99 - 98 % health.
Thats i understand. Than how it can be than in case of 8035 all of them is like that and there is no 99 or 98 or any other values. Only 90 and 87 ?
 

Pivot

E*POWAH Master
Jun 11, 2020
668
1,088
New Forest, England
Yes and No, because IF the health (capacity) reading is degrading rapidly, it always does it that way (90/10, 87/20...) but some people state that they have charged their battery, say 30+ full cycles and see e.g. 99 - 98 % health.

I wonder if they use the same or diff software version.
 

Milan

Member
Sep 9, 2020
91
34
Czech Republic
Very good point GM!

We need to understand the Shimano logic and equally important what is the optimal use of this technology.

From the logic perspective, Shimano states that we should have 60% capacity left after 1000 cycles. That doesn’t add-up in my Kopf, when I had 90% at 10 cycles and now 87% at 20.

I understand that Lithium-Ion based batteries don’t like to be left discharged, but also don’t like being left continuously on a charger. I charge my bike after every ride and I store it charged for when I get a cabin-fever and I need to clear the cobwebs in my head.

Tesla has probably the most advanced battery management capability. Apple is pretty good as well. Shimano might be equally good, but sadly it is not as well published.
Your comment only leads me to the thread on E8035 and my answer is still the same: BT-E8035 is a poor design and the stats provided elsewhere only prove that. The stats more or less show that they are very consistent in how the batteries degrade the same way, i.e. very fast. If it is the BMS and this BMS decides that every time you use your bike it will ‘sacrifice’ some portion of the cells, you can call it a ‘software/firmware’ issue, some call it a bug. I call this whole thing a design. The E8035 is designed to degrade this fast. Consequently or in the long run, it is not as fast as you would expect if you are a random biker. If you are a busy biker you know very fast that there is something fishy about E8035….
 

Milan

Member
Sep 9, 2020
91
34
Czech Republic
No, it also happen with my BT-E6001 (500Wh rack mount) and E6100 motor never used for steep hills. Most flat roads and normal assistance (city bike).
90 % health @ 10 charge cycles
87 % health @ 20 charge cycles . Bike now at 2200 km and 26 Cycles.
I'm unsure if it is a software bug. The input Wh per full charge has not changed significantly since the battery was 100 % healthy.
It's a very controversial issue - In a German Forum there are now over 2810 posts (and counting) about the very same issue. That tread started 3½ years ago!
Could you please post the link on this issue?
 

Pivot

E*POWAH Master
Jun 11, 2020
668
1,088
New Forest, England
Your comment only leads me to the thread on E8035 and my answer is still the same: BT-E8035 is a poor design and the stats provided elsewhere only prove that. The stats more or less show that they are very consistent in how the batteries degrade the same way, i.e. very fast. If it is the BMS and this BMS decides that every time you use your bike it will ‘sacrifice’ some portion of the cells, you can call it a ‘software/firmware’ issue, some call it a bug. I call this whole thing a design. The E8035 is designed to degrade this fast. Consequently or in the long run, it is not as fast as you would expect if you are a random biker. If you are a busy biker you know very fast that there is something fishy about E8035….

Well, I have E-8010 with the same degradation pattern as E-8035, which leads me towards the software, as I would expect internal design of the respective batteries to be different.
 

jimbob

Active member
Aug 3, 2020
518
429
East UK
Your comment only leads me to the thread on E8035 and my answer is still the same: BT-E8035 is a poor design and the stats provided elsewhere only prove that. The stats more or less show that they are very consistent in how the batteries degrade the same way, i.e. very fast. If it is the BMS and this BMS decides that every time you use your bike it will ‘sacrifice’ some portion of the cells, you can call it a ‘software/firmware’ issue, some call it a bug. I call this whole thing a design. The E8035 is designed to degrade this fast. Consequently or in the long run, it is not as fast as you would expect if you are a random biker. If you are a busy biker you know very fast that there is something fishy about E8035….
I think its worth remembering that we still don't know if the reported values of battery health are accurate or not.

I've been tracking the input power to charge the batteries for a while now, and think I have an accurate method down. It seems like there is quite a difference in capacity between a new battery i have and one with 50 cycles. I want to gather more data before showing my results though.
 

guika

Member
Oct 31, 2020
33
11
HU
I think its worth remembering that we still don't know if the reported values of battery health are accurate or not.

I've been tracking the input power to charge the batteries for a while now, and think I have an accurate method down. It seems like there is quite a difference in capacity between a new battery i have and one with 50 cycles. I want to gather more data before showing my results though.
That makes a lot sense... looking forward to it.
 


TG1971

Member
Nov 14, 2020
47
15
Yorkshire
My battery is now down to 81% after 41 cycles rode Dalby forest red route and ran out of battery at the end only used eco it’s 21 mile and 2300ft climbing trail centre in dry, plugged my bike into E-TUBE with Sm-pce02 and the report now doesn’t show battery health the new update has removed it, has anyone else noticed this?
 

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