Shimano Battery Life Poll

RickBullotta

E*POWAH Elite World Champion
Jun 5, 2019
1,743
1,488
USA
Hi, all. I'm trying to get to the bottom of why remaining capacity deteriorates quickly for some riders and less so for others. Shimano tech support was of little or no help.

What I'd ask you all to post is the following three pieces of data (two of which you'll need to get from the diagnostics in the eTube app):

1) # of charging cycles
2) remaining capacity
3) which charger you use (fast (E6000) or slow (E6002) charger)

Anecdotally, it seems that the fast charger has a very negative effect on battery life. Obviously there are lots of other factors, but if I have this dataset I can start doing some analysis.

Thanks!

Rick
 

nosenada

Member
Nov 26, 2019
50
29
California
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.
 

Fx1

Auto WARNING : Possible Duplicate user : "Zero"
Feb 6, 2020
267
203
GB
Never fast charge. Always store inside and not in the cold.

The cells in standard shimano batteries are not as good as the ones in the decoy or levo which use better cells.

This is possibly a factor
 

RickBullotta

E*POWAH Elite World Champion
Jun 5, 2019
1,743
1,488
USA
Never fast charge. Always store inside and not in the cold.

The cells in standard shimano batteries are not as good as the ones in the decoy or levo which use better cells.

This is possibly a factor

That's a theory I'm trying to validate. Some manufacturers ship the E6000 fast charger, some don't. Once I have some concrete data to support it, I'm going to ask that Shimano and the manufacturers make this clear in their documentation and manuals. It's absurd that a battery should lose 7-10% of its useful capacity after 20-40 charging cycles.
 

nosenada

Member
Nov 26, 2019
50
29
California
I agree loss of 7-10% in 20-40 cycles is pretty bad. My experience of 15-17% is awful.

It is interesting to note that Shimano recently changed its published specs on its slow chargers (e6002).

Shimano used to state charge rates of 0-80% in 4 hours then 80-100% in 3.5 hours for the e6002.

Now Shimano claims 0-80% in 6.5 hours and 80-100% in 7.5 hours.

Most websites selling the e6002 still have the old charge rates published.

The new published rates are closer to my observations for my slow charger.

I find it odd that the fast charger takes over twice as long (2.5 hours) to charge the last 20% than the slow charger (1 hour). Because of this I suspected my slow charger was damaging my battery by charging it too fast during the last 20%, but if others are having similar degradation from only using the fast charger then maybe it simply the battery or perhaps discharge rate.

I doubt environmental conditions in my case as I live in a temperate climate 40-80 deg F, store my batteries between 40-60%, never leave my batteries in a hot car, and never charge my batteries below 50 deg F.

Worse abuse they get is a once a week 100% discharge and an occasional turbo run directly to a fast charge where the pack is a bit warm, but that is not often.
 

MassDeduction

New Member
Dec 1, 2019
49
25
Victoria, BC
Never fast charge. Always store inside and not in the cold.

The cells in standard shimano batteries are not as good as the ones in the decoy or levo which use better cells.

This is possibly a factor

Except the "fast charger" isn't charging that fast. For example, my 504 Wh Shimano battery is 14 Ah, and the faster charger is 4 amp. Dividing 4/14 gets you 0.286, so a charging rate of .29C when you round off. Anything under .50C is considered a relatively safe charging rate, with lower being better until you hit .25C at which point there's no benefit to going lower still (at least not when you're charging the first 80% of the battery). So .29C is not only in the safe range but is closer to the ideal end of the safe range than the top end.

I've been using the slow charger and using a timer to make it cut out at about 80%, but I occasionally go over. As others have noted, I have also seen it fail to slow down at 80%. The slow charger is 1.8A, which yields a charge rate of .13C, so it's well below the ideal slowest charging rate.

Shimano appears to have discontinued their compact slow charger and replaced it with a compact 4A "fast" charger version (again, with the caveat that it's not actually that fast, just not as slow as the old one). Yes the slow charger over thousands of charges might be slightly gentler, but really only slightly. If the fast charger rate drops to a quarter of it's normal rate for the top 20%, it would be charging the last 20% at .07C, which is admittedly nearly twice as slow as the .13C standard charging rate of the slow charger. But both rates are pretty darn slow, and that may be why the slow charger doesn't bother to slow down further.

Protip: if you have to charge the battery in a cold space, remove the battery from the bike and lay it on top of the charger. The charger gets warm as it charges, which could bring the battery up to a better charging temperature. If the charger gets too warm, then maybe put something between the two of them that will slow the rate of heat transfer (or spread the heat over a wider area). :)
 
Last edited:

MassDeduction

New Member
Dec 1, 2019
49
25
Victoria, BC
I agree loss of 7-10% in 20-40 cycles is pretty bad. My experience of 15-17% is awful. [...]

Shimano warrants these batteries to have 60% of the original charge after 1000 cycles. The battery life you're suggesting is absolutely terrible. So much so, that you might be in a warranty situation after 1000 charges. So keep that in mind! You've got me curious enough to check my own battery. How are you guys measuring it? The Etube app, or some other way? I can't use Etube as I'm using an old firmware and don't want it to update. Well, I suppose I can put the battery in a bike with an up to date firmware and check it.
 

RickBullotta

E*POWAH Elite World Champion
Jun 5, 2019
1,743
1,488
USA
Shimano warrants these batteries to have 60% of the original charge after 1000 cycles. The battery life you're suggesting is absolutely terrible. So much so, that you might be in a warranty situation after 1000 charges. So keep that in mind! You've got me curious enough to check my own battery. How are you guys measuring it? The Etube app, or some other way? I can't use Etube as I'm using an old firmware and don't want it to update. Well, I suppose I can put the battery in a bike with an up to date firmware and check it.

I’m using the eTube app on a laptop with the PC-whatever USB to eTube box.
 

mtbbiker

Active member
Sep 15, 2018
111
114
Murrieta
Hi, all. I'm trying to get to the bottom of why remaining capacity deteriorates quickly for some riders and less so for others. Shimano tech support was of little or no help.

What I'd ask you all to post is the following three pieces of data (two of which you'll need to get from the diagnostics in the eTube app):

1) # of charging cycles
2) remaining capacity
3) which charger you use (fast (E6000) or slow (E6002) charger)

Anecdotally, it seems that the fast charger has a very negative effect on battery life. Obviously there are lots of other factors, but if I have this dataset I can start doing some analysis.

Thanks!

Rick
Hi Rick, Good topic!
I didn't pay attention to my charging cycles until about last month. My 1st bar at my normal riding area last just over 5 miles. Last month the 1st bar dropped at about 1.2 miles. I thought it was a fluke, but charge after charge and 1st bar always dropped around 1.2 miles.

I took my bike in with all the data you are asking for and Shimano claims at this point, this is normal. My bike shop says I have a 2yr warranty. Hopefully the battery is stabilizing, I believe I've lost about 10 miles in my range as a result. The next bars last about 4 miles each or so before dropping. Yesterday I got a 20 miles ride in with just over 2,500ft of climbing in mostly Trail mode set at 70%. Came back with last bar flashing. My longest ride was about 30 miles and just over 3,000ft of climbing. I weigh about 210lbs.

Here is what you asked for:
1) 138 cycles
2) 87%
3) EC-E6000 charger
4) Battery BT-E8010

My Tazer is about 8 months old, I ride about everyday and sometimes twice a day, that why there are so many charge cycles. I'm surprised that some of you have less charge cycles and a lower remaining capacity.
Thanks,
 

nosenada

Member
Nov 26, 2019
50
29
California
Where do you get the special cable from as never knew one existed and it's a bummer that you can't get the battery info on the phone app :confused:

You can get it from your phone as @mtbbiker mentioned by using the apps Emaxx or Stunlocker.

It is only the official Shimano phone app, e-Tube, that does not supply this info.
 

MassDeduction

New Member
Dec 1, 2019
49
25
Victoria, BC
Where do you get the special cable from as never knew one existed and it's a bummer that you can't get the battery info on the phone app :confused:

Shimano dealers can sell you the special cable. Bike shops can order it from Shimano, it has a retail price, and they are allowed to sell it. It's expensive, though.
 

JimBo

E*POWAH Elite
Jan 3, 2019
216
362
Western MA, USA
10 months, 31 cycles, 100% remaining, 4A charger.

Addendum: When not using the bike - a 2018 Commencal Race Fox - for a few days or more, I maintain a charge level of 40-60%.

On my previous e8000-equipped bike (Motobecane HAL eBoost Pro), I was less mindful about that and would charge to full after each ride, even if I knew I may not be using it for several days.

I sold that bike with 23 charge cycles at 97% capacity after a bit more than a year.
 
Last edited:

RickBullotta

E*POWAH Elite World Champion
Jun 5, 2019
1,743
1,488
USA
1) 40 cycles
2) 98%
3) EC-E6000 charger
4) Battery BT-E8010
5) 2919 km
6) 12 months

That's where it gets interesting. I'm almost exactly the same stats as you (cycles, charger, battery, age, total distance), but I'm at 93% instead of 98%.
 

Cyclopath1000

Active member
Apr 26, 2019
309
125
Davis Ca
I have a commencal meta 650 b with the e8000 and 6000 fast charger . Got it may 2018 right after sea otter. 150 miles on odometer and 120 or so hours. Got a second batt about three months ago because the original seemed to work flawlessly to two bars and then poof nada. So I once at my shop tried to inquire via etube on the shops puter and even with Shimano on the line we couldn't make anything happen so basically no updates since inception. Original batt stored charged and used yesterday and today. So while I didn't do an epic ride to drain. But come on comrades, your cellphone battery is what two years and trash , your laptop ...... All your "scientific " calculations based on an app that measures your batteries. ...and u believe it means something !! All I know is that put $3-4 or or 3 eu or some number of talents of gold in a jar and plan on a new battery every two years. The next one will be a rebuild of my original one by a firm in city of industry ,ca.

Screenshot_20200307-170545.png


IMG_20200307_170553.jpg
 

papab

Member
Jun 10, 2018
89
45
colorado
Cyclopath, the battery should last longer than 2 yrs. I get a lot more than that out of a cell phone battery. Don't leave it charged at 100%.
 

Cyclopath1000

Active member
Apr 26, 2019
309
125
Davis Ca
All I'm trying to say is that even if all this effort actually is valid we are talking about $2.50/ week if you get a new battery or $1.00/ week if there is an industrial.quality rebuilder around. Now I agree that if the batt now dies before your ride is over , that's an issue. If my rides were over 4,000 feet elevation and 25 miles of singletrack length routinely , all the battery issues take on a new dimension. My neck and shoulders are so chronically janked 69 yo who rides 3-7 days a week , that I even stopped carrying a pack , so sticking a second batt in a pack is a non starter. Newer cells that put out individually greater volts also will be non starters if the end voltage exceeds the Shimano design. This coming summer when I'm spending time in mendocino I will take the old battery and see what it does as in ride until dead. My above post is basically showing that the initial first hour or so of my usual battery use seems absolutely unchanged from when new. And again it's only later in a ride that the battery life deterioration is evident. From my reading it has something to do with probably one or more relatively bad cell in one of the five stacks of 10 cells in the e8000 battery. That one cell can be tested for and replaced but unless you are a wizard the process of tack welding each cell to it's respective stack is best done by some kind of automated device.
 

R120

Moderator
Subscriber
Apr 13, 2018
7,819
9,185
Surrey
I cant remember my mileage, guessing around 2000 or so on one of my bikes, and the battery from that has gone from being able to do my 25 mile local loop in trail mode, about 1500ft of elevation, to now only being able to do 20 in trail
 

Cyclopath1000

Active member
Apr 26, 2019
309
125
Davis Ca
Plus I almost never ride boost with the exception of the e bike race at sea otter last year. Now that it's cancelled I basically always ride in trail and always try to put my legs into it. I guess if I lived elsewhere than NorCal the whole way I approach the sport might be radically different.
 

Cyclopath1000

Active member
Apr 26, 2019
309
125
Davis Ca
R120 .. that's again one or two bad cells. That's why I purchased a second battery and will watch the old one to see if it drops again by 20%. When that happens I'm sending it to the place in city of industry and let them test it and either put in all new cells or replace the few weak ones.

I'm a bit interested as the excellent ride I posted ...I'm wondering if the extensive rest while fully charged (months ) managed to equalize the cells. I'm just not in the mood to ride to battery shutdown now.
 

R120

Moderator
Subscriber
Apr 13, 2018
7,819
9,185
Surrey
I have 3 batteries that I rotate, but one has had a lot more use than the others.

My longer distance rides tend to be around the same area, so I will tend to loop back to my car and swap out for more range
 

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