Shimano Battery Life Poll

[jimbob]

Just hit 40 cycles today with the E8035, and has now dropped to 82% remaining battery health.

Eco reserve lasted for a while 2s when the battery died. Not very impressed!

I'm going to keep going with this battery for a while I think just out of curiosity before doing a warranty claim. Santa should be bringing me a nice new one tomorrow which I can use for longer rides and to compare against.

 

[Growmac]

Just hit 40 cycles today with the E8035, and has now dropped to 82% remaining battery health.

Eco reserve lasted for a while 2s when the battery died. Not very impressed!

45 cycles and 82% here. Eco reserve lasted 37 metres according to my GPS today.

 

[jimbob]

Just done a charge from flat and its taken a total of 470wh of electricity. As that also includes loss of the charger and battery itself, its a long way short of the 504wh it should be!

Even with the battery reporting 82%, thats still short, so likely the problem is worse than first thought unfortunately.

 

[Dave_B]

How do you measure the wh going into the battery during a charge?

 

[OleP]

How do you measure the wh going into the battery during a charge?

I measure in the same Wh range as Jimbob ( 470 - 500 Wh) and use a cheap energy meter that I have compared with the 'official' meter, installed in my house by the electricity compagny and found it relatively accurate (<5% difference). It compensate for the 'Power Factor' (Cos. phi).
Example link to AliExpress: energy meter – Buy energy meter with free shipping on AliExpress
Probably also deliverable from eBay and Amazon. I just bought mine at a local hardware store some years ago.

 

[jimbob]

...or worse that first thought?

Ah, yes. My bad! Edited to correct.

Weather was rubish today so havent had the chance to empty the new battery yet to compare. I did repeat the test with the 82% battery though and got within a few wh, which shows the measurement is consistent which is good.

 

[jimbob]

How do you measure the wh going into the battery during a charge?

As above, with a mains power meter. It's not a great measure as there are losses in the charger and in the battery itself, so the power the battery takes will always be less than that measured as going into the charger. So for a 504wh battery, the power in should be above the battery capacity, when it's well below.

What the test does give is a comparison; both to a new battery I have and then over time against each of the batteries to see if the reported values match those measured.

I've also just got a E6004 fast charger, so doing some comlarisons of that. I'd also like to test the difference charging in the cold has as I think the capacity may be reduced more than I thought.

 

[Dave_B]

So I bought a meter and this is the result from a fully depleted battery

 

[RickBullotta]

So I bought a meter and this is the result from a fully depleted battery

View attachment 48431 View attachment 48432

Factoring in charging losses, it does seem that 85% is a reasonable estimate, correct?

 

[Dave_B]

I’ve no idea mate to be honest? Would there be 15% losses through the charger?

 

[RickBullotta]

I’ve no idea mate to be honest? Would there be 15% losses through the charger?

Electric cars have about a 15% charging loss. That's the closest analog I could come up with.

 

[jimbob]

So I bought a meter and this is the result from a fully depleted battery

View attachment 48431 View attachment 48432

Interesting. What charger were you using? Seems to have been quite a fast charge at just over 3.5hrs?

Just done the test with the brand new battery and measured 516wh, so lower than I would have thought still. I have been assuming 5% loss from the charger and 5% from the battery, but no way to tell.

Given the above values, and asuming both batteries had the same initial capacity, it would show my one battery has degraded by 9% giving 91% relative to new (470wh/516wh). Battery is showing 82% in STunlocker, so in theory better than reported. 9% at 40 cycles seems more like what I'd expect to see.

All charges were done at 20C on a E6002 charger once the batteries had normalised. The meter wont be that accurate, but will give relative changes.

 

[Dave_B]

This charger

 

[jimbob]

This charger View attachment 48443

Thanks. That may explain why yours readings are slightly higher than mine as thats an older charger and so probably less efficient.

I ran the test with both the E6002 (1.8A) and E6004 (newer 4A charger) and got readings 5wh apart which is good.

Again, it's all relative so only way to tell is keep measuring the same battery with the same kit.

 

[OleP]

There are losses in battery when charging as well as losses in the charger. In battery from internal resistance as well as from chemestry.
My GUESS is that this loss is at least 20 % and added to the charger loss it sums up to at least 30 - 35 %.
I think is is really difficult to measure/calculate the actual losses in the chain from the mains output to the actual useable WattHours inside the battery cells.
My measurements at a E6001 (504 Wh) battery with less than 15 cycles shows charging Wh in the range from 470 to 507 Wh, so very comparable to db3266's measurements.
By the way, one does not have to charge a completely flat (0 %) battery to 100 % to calculate the battery capacity (that is also bad for the battery lifetime). This formula will do it:
Wh(Meas) / (SOC(after) - SOC(before)) * 100 = Wh(capacity) SOC= State Of Charge (%)
Of course the result gets more accurate with higher charge %, but I've got acceptable results with charging from 15 to 90 % as well as charging from 30 to 60%. I have no idea why lots of Shimano batteries report only 90 % health after just 10 full charges and even 85% efter 25 charge cycles, but I may have an idea why almost everybody measures lower wattage (also in some German forums) than expected, and I'll try to explain my theory in a later post (it takes me long time to write in English).

 

[OleP]

Again, it's all relative so only way to tell is keep measuring the same battery with the same kit.

Yes, that is a very good statement, and also keep track of range/full charge or maybe range/Wh. Best followed in a spreadsheet chart.

 

[jimbob]

I also have a theory that charging the batteries when cold, such as outside in the garage, has a significant impact on the usable capacity. I'm running the test at the moment.

 

[OleP]

I also have a theory that charging the batteries when cold, such as outside in the garage, has a significant impact on the usable capacity. I'm running the test at the moment.

Please never ever charge Li-Ion batteries in the cold! Do it at room temperature. If after a cold ride, let it warm up inside house for an hour or so before charging.
Charge at cold is likely number one reason to reduce life span.

 

[jimbob]

Please never ever charge Li-Ion batteries in the cold! Do it at room temperature. If after a cold ride, let it warm up inside house for an hour or so before charging.
Charge at cold is likely number one reason to reduce life span.

Agreed, but this one will be going back under warranty at some point, and doubt a single charge will damage it too much.

All in the name of science!

 

[JJT]

Normal or not?

2018 bike, external E8010 battery. Factory settings exc. EU-->US.

Not sure how fast battery health drops 83%.

Two of my latest rides:

Super easy trails, aggressive riding, trail mode 100%, temp. +5c = Empty battery

Easy trails, normal riding, eco mode 90% + trail 10%, temp. -1c = Empty battery

Edit: Rider weight 90kg. Both rides autopause OFF.

 

[Gary]

are you saying you used up a fully charged 504wh battery in just 17.8km and 181m of ascent in trail?
when your average speed wasn't even 10mph?
If so that's terrible range.

What do you weigh? What tyres were you using? and what were the riding conditions?

 

[JJT]

are you saying you used up a fully charged 504wh battery in just 17.8km and 181m of ascent in trail?
when your average speed wasn't even 10mph?
If so that's terrible range.

Yes

What do you weigh? What tyres were you using? and what were the riding conditions?

Weight 90kg. Tyres DHF+DHR. Cold and wet but very fast rolling trails.

 

[Gary]

Yeah. that's terrible. Even with those tyres. are they both DH casing and Maxxgrip compound? and what pressures do you run?
My last ride a few hours ago was around 20km and 250m but the entire ride was natural muddy or snow (so fairly hard going) and I finished with 3 bars left.
My battery is also down to around 83% health but has done more mileage than yours. (can't remember how many charge cycles)
I'm slightly heavier than you too.

 

[JJT]

Yeah. that's terrible. Even with those tyres. are they both DH casing and Maxxgrip compound? and what pressures do you run?

Rear DH MaxxGrip, front Dual Exo. Not sure the pressure but "safe" anyways.

My last ride a few hours ago was around 20km and 250m but the entire ride was natural muddy or snow (so fairly hard going) and I finished with 3 bars left.
My battery is also down to around 83% health but has done more mileage than yours. (can't remember how many charge cycles)
I'm slightly heavier than you too.

My 13km tarmac commuting takes 2 bars

 

[Gary]

Rear DH MaxxGrip, front Dual Exo.

Dafuq would you run a super soft compound on the rear and a hard compound up front for?
That rear tyre if run at low(ish) pressure is robbing you of 60w

My 13km tarmac commuting takes 2 bars

That's also ridiculous.
My commute is 10 miles with 900ft ascent each way and I use one bar riding it at a 20mph average speed (dual compound DHF/SS both at 50psi+

 

[Zimmerframe]

Normal or not?

That does sound like impressively low range/climb even with 400wh battery. With about 450wh on my Shimano with DHF/DHRII in Trail and riding hard with 90%+ off Road I'd expect 30-40km's and 1000m climb.

Do you pedal with a low cadence ? That would super suck your power and convert most of it to heat instead of power ?

Even on my Kenevo, which has always been a major battery gobbler, it's pretty rare to get less than 20km's and 1000m+ in an hour riding like a complete maniac (all modes) out of my remaining 450wh. That's with DH22's.

Do you have a heated saddle ? I notice the low temperatures ! ?

 

[JJT]

Dafuq would you run a super soft compound on the rear and a hard compound up front for?
That rear tyre if run at low(ish) pressure is robbing you of 60w

Yep, not the best combination. I decided to run out that old DH tyre before buying new ones. Anyway I think the tyres or pressure not explain 17km range

Any FACTS about Shimano warranty after STUnlocker use? Found only one motor case:
"I didn't go crazy with my motor, I just used STUnlocker, or Stepsunlocker as it was at the time, to change the market and a few power levels. Changed everything back to stock before returning it to LBS and the motor was replaced without issues."
I´m ready to buy a new battery but sure I use warranty if possible. And who knows if this is motor problem

 

[gtaadicto]

The other day I rode 35.5 km with 450m elevation and used 417 Wh, and I thought that was a low range.

Yours is definitely not normal.

By the way, the temperature was only 1⁰C and the soil was wet. The battery capacity is at 88% after 6000 km.

 

[JJT]

That does sound like impressively low range/climb even with 400wh battery. With about 450wh on my Shimano with DHF/DHRII in Trail and riding hard with 90%+ off Road I'd expect 30-40km's and 1000m climb.

My longest ride ever was 42km. Summer conditions, rolling tyres and motor off time to time. It was over a year ago.

Do you pedal with a low cadence ? That would super suck your power and convert most of it to heat instead of power ?

I don´t think so

Do you have a heated saddle ? I notice the low temperatures ! ?

Not even cold yet!

 

[Gary]

I´m ready to buy a new battery but sure I use warranty if possible. And who knows if this is motor problem

What? You're just mentioning now that you're using STunlocker?
You do realise the motor uses more battery when motor assistance no longer stops at 15mph? and ANY climbing above 15mph uses tons more battery. This combined with a super draggy rear tyre is probably contributing far more to your range issues than you realise.
Stick a fast rolling rear tyre on, inflate it to 30psi and reset your settings to limit it to 15mph and then do a similar ride.

I use warranty if possible.

Shimano Steps batteries are rated to retain at least 60% of their original battery capacity after 1,000 charging cycles (pretty much impossible to manage within the 2 year warranty period). so yours if showing 83% you're wasting your time trying to get it warrantied.