Unfortunately its not quite as simple as that (wish it was). Really, you want a stable fixed resistive load and then measure voltage and current over time to give you the power output. Unfortunately the battery outputs are electronically switched which makes that very difficult to do. I would give it a go, but the cost of the batteries and risk of damaging them puts me off somewhat!
Shimano BT-E8035 Integrated Battery Issue: very fast degrading and loss of range
- Thread starter Milan
- Start date
Rich-EMTB-UK
E*POWAH Master
As am about to move to a Shimano based bike from my Turbo Levo this seems quite a concern but there again I was reading horror stories before I got my TL in 2019 and have had zero issues with that motor/battery combination which both show 100% health still and have been totally water proof and no drop in range.
So I guess like all electrical products some work better than others and some folks are just plain unlucky.
So I guess like all electrical products some work better than others and some folks are just plain unlucky.
Best to buy a Shimano bike with a third Party battery then. Then you won't have that Problem.
Rich-EMTB-UK
E*POWAH Master
didn't realise there were third party compatible batteries available, will check it out if I have a problem thanks
shite in = shite out
I think you missed my point bro
Rich-EMTB-UK
E*POWAH Master
poor quality in = poor quality outI probably did
Milan
Member
- Thread starter
- #191
Well then, I did understand well. Knowing that Shimano is familiar with that and puts the crap in and gets the crap out (known issue) is a form of lie as they simply cannot meet their advertised cycles and provide appropriate capacity of the battery in the long run.poor quality in = poor quality out
You got that wrong. If you want to avoid that Problem and still ride a Bike with Shimano Motor get a bike designed with a battery from a third party like the New Santa Cruz Heckler or Focus Jam they come with a Darfon battery.
But if they are more reliable is another topic
But if they are more reliable is another topic
It´s only possible with laboratory mesaruments directly on the battery using a dc load and datalogger.
Fortunately i have both, the lab and a new battery so in the next months i plan to start using it and tracking capacity on the lab vs life indicated on the Shimano Display
Pivot
E*POWAH Master
I do get the desire to measure degradation of battery, and charging cycles is accepted unit of measure, however…
I am more interested how many km I can travel on the bike and battery charge.
Here are my numbers:
998km, 8 cycles, 100% health
I am more interested how many km I can travel on the bike and battery charge.
Here are my numbers:
998km, 8 cycles, 100% health
mad115
Member
is there really no Chinese alternative to the BT-8035?
I have two ebike with BT-8035 ;(( Each with different motor (E8000 and E7000) but degradation issue is same on both ebikes.
I have two ebike with BT-8035 ;(( Each with different motor (E8000 and E7000) but degradation issue is same on both ebikes.
mad115
Member
Milan
Member
- Thread starter
- #205
If your batteries are still warrantied, you only need to contact your retailer. Depending on the %, you will get a respond what to do. If your are above 80% (means that you have not reached the magical 5K km), most likely you will be asked to go under. If your Shimano dealer is currently with 0 batteries, the scenario may alter. If your warranty is not a rolling one and your bike is "out of service" for a month, your warranty will only extend by one month, i.e. with the next (2nd) battery you have to be fast and make 5K km as quick as possible and use your warranty again because you will have to do the same with the 3rd one too. Then you can claim your bike is not fit for purpose and can claim your cash back. Knowing this and having this discussed with a number of people, I consider this battery a fraud and think all owners globally should jointly make a claim.
mad115
Member
As i wrote recently, i have two ebike. I give here a summary of how I stand.
Unfortunately both ebikes I have with Shimano BT-E8035 batteries:
MERIDA eBIGnine E7000 1600km 20cycles 87% healty
CTM E8000 4500km 50cycles 80% healty
Although they each have a different engine; as well as a computer; they both behave exactly the same.
The behavior of the battery in Merida is the same as in CTM. After every 10 charges, the battery is degraded (by a few percent).
And of course the range is adequately shorter ..
This is a visible firmware error in the Shimano BT-E8035
Today I do not recommend anyone to buy a bike with BT-E8035 because it is incorrectly designed.
Unfortunately both ebikes I have with Shimano BT-E8035 batteries:
MERIDA eBIGnine E7000 1600km 20cycles 87% healty
CTM E8000 4500km 50cycles 80% healty
Although they each have a different engine; as well as a computer; they both behave exactly the same.
The behavior of the battery in Merida is the same as in CTM. After every 10 charges, the battery is degraded (by a few percent).
And of course the range is adequately shorter ..
This is a visible firmware error in the Shimano BT-E8035
Today I do not recommend anyone to buy a bike with BT-E8035 because it is incorrectly designed.
Are the batteries actually degrading by the reported amount then?
My battery was showing 78% after 60 charge cycles, but the range, while less than new, wasn't down 22%
l would still get 30 miles of range where l could manage maybe 33 if l was lucky, when it was new. I sent the battery back and was sent a new one under warranty.
As that took over 2 months, l bought another battery, and despite being a brand new one it just about manages 30 miles on a full charge.
l am wondering if the drop in "battery health" is an issue with the BMS software rather than an issue with the actual cells in the battery.
Has anyone experienced a fall in actual range to coincide with their reduced battery "health" ?
For example if your battery is showing under 80% has your range actually dropped by over 20%?
So if you were getting 40 miles on a full charge you would be closer to 30 miles now.
l would still get 30 miles of range where l could manage maybe 33 if l was lucky, when it was new. I sent the battery back and was sent a new one under warranty.
As that took over 2 months, l bought another battery, and despite being a brand new one it just about manages 30 miles on a full charge.
l am wondering if the drop in "battery health" is an issue with the BMS software rather than an issue with the actual cells in the battery.
Has anyone experienced a fall in actual range to coincide with their reduced battery "health" ?
For example if your battery is showing under 80% has your range actually dropped by over 20%?
So if you were getting 40 miles on a full charge you would be closer to 30 miles now.
Of course its Software related, shimano uses normal cells like every other brand.
Were it cell related not every battery would degrade exact the same amount in the same cycles.
So its out of question that its the Software that absolut shit. I wonder when the first batch with better software comes to the market.
They should handle it like bosch that the batterys are also updateable.
Can't believe it that they can't fix that Problem
Were it cell related not every battery would degrade exact the same amount in the same cycles.
So its out of question that its the Software that absolut shit. I wonder when the first batch with better software comes to the market.
They should handle it like bosch that the batterys are also updateable.
Can't believe it that they can't fix that Problem
Last edited:
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