Charging methods - battery health

[Nautonier]

The smartphone and tablet versions of the E-Tube app are not the same. The tablet version gives you the battery diagnosis with charge cycles and remaining capacity.

The charging methods will not damage the cells the only difference between them can be the effect on the capacity. According to Shimano, the loss of 10% in a year is OK so in two years you can go down to 80% which will be considered as normal. Personally, I would like to keep it higher than that.
My two batteries are on 99% after a year, splitting the use almost equally. I put the question in the first post waiting for others to chime in to see if there is a real-life difference between charging methods and how fast the battery capacity goes down after a number of charging cycles...

Good to know, I don't have an iPad but I looked at the app on my wife's one and at a glance it looked the same as the iPhone version.

I'd also be interested to see if anyone who has had batteries for a year and has just charged them up to 100% every time after a ride has the same or less capacity than you do. I'd like to keep my batteries in the best condition possible (they're expensive!), so will be adopting your method of charging/rotating just to be on the safe side.

 

[Tamas]

So if I really look after my battery and keep it in tip top condition, then go for a winter ride at say 0 degrees, have I gained any advantage or does the battery just get cold and I loose any advantage of keeping it warm?

Not had my bike for a winter to form a view on the effects.

Generally, batteries don't like and don't function well in cold. I had one winter with my ebike and experiencing how quickly the range went down in the cold (I rode down to -5) I put a neoprene cover on it and it improved the range significantly. I have a bike with an external battery so it's easy to do it. You decide for yourself based on your riding and preferences...

 

[Tamas]

Good to know, I don't have an iPad but I looked at the app on my wife's one and at a glance it looked the same as the iPhone version.

I'd also be interested to see if anyone who has had batteries for a year and has just charged them up to 100% every time after a ride has the same or less capacity than you do. I'd like to keep my batteries in the best condition possible (they're expensive!), so will be adopting your method of charging/rotating just to be on the safe side.

I put the iPad screenshots in one of the comments above, you can see it there. I have the bike for a year and I just discovered this not too long ago. I always used my phone to change the settings and do the firmware upgrades and I thought the table version is the same but turned out it isn't.

 

[Levo Lution]

The smartphone and tablet versions of the E-Tube app are not the same. The tablet version gives you the battery diagnosis with charge cycles and remaining capacity.

The charging methods will not damage the cells the only difference between them can be the effect on the capacity. According to Shimano, the loss of 10% in a year is OK so in two years you can go down to 80% which will be considered as normal. Personally, I would like to keep it higher than that.
My two batteries are on 99% after a year, splitting the use almost equally. I put the question in the first post waiting for others to chime in to see if there is a real-life difference between charging methods and how fast the battery capacity goes down after a number of charging cycles...

Does it mean that if you buy an old model that has been in a stock for a year, capacity of the battery can only be 90% for a new bike?

 

[Tamas]

Does it mean that if you buy an old model that has been in a stock for a year, capacity of the battery can only be 90% for a new bike?

With the 10%/year loss in capacity Shimano refers to one year of regular use. The bikes in stock have their batteries in sleep mode so they can be stored without degrading the battery. If the dealer ‘wakes it up’ but stores it properly then no degradation either, the battery health should be 99-100% after a year.
With Specialized MC and Shimano E-Tube app the actual state of the battery can be checked even by the user and Bosch dealers can check Bosch batteries.

 

[Nautonier]

Does it mean that if you buy an old model that has been in a stock for a year, capacity of the battery can only be 90% for a new bike?

If it had been stored at extremely high or low charge yes.

 

[Gary]

Simple rule a knackered battery is the perfect wife excuse for a new bike.

I wonder if I should heat the garage and wrap the bike in cotton wool?

Wife in the garage, Bikes in the bedroom is my solution

 

[Gary]

My two batteries are on 99% after a year,

What makes you think the Tablet App's diagnosis is accurate to 1%?
[/bornCynic]

 

[highpeakrider]

Wife in the garage, Bikes in the bedroom is my solution

I’ve got 2 spare bedrooms in a bungalow so could have the best of both worlds ?

 

[Tamas]

What makes you think the Tablet App's diagnosis is accurate to 1%?

When did I tell that the diagnosis is accurate to 1%??? It shows what it shows and the only way of knowing/guessing the accuracy is the change in the range. The app just reads the info it gets from the bike (BMS or wherever). I checked it, I got exactly the same report and numbers when I ran it on a PC through the SM-PCE02 in my friend's bike shop.
Since I didn't notice any change in the range and I can still make 1400-1500m elevation with one battery I guess the diagnosis is close enough to reality. If the range drops 10% and the diagnosis will still show 99% remaining capacity then I know it's way off... it's not rocket science.

 

[MattyB]

I would love to know how they are determining these battery health figures, then we could determine how much value there is in using them...

 

[Tamas]

I would love to know how they are determining these battery health figures, then we could determine how much value there is in using them...

"SoH evaluation:
- First, a battery management system evaluates the SoH of the battery under its management and reports it."

State of Health

 

[Gary]

When did I tell that the diagnosis is accurate to 1%???

The second you quoted your battery at 99% health

 

[Tamas]

The second you quoted your battery at 99% health

I just quoted what's in the report I didn't comment on its accuracy or claimed that it's accurate to 1%. But hey, if it makes you feel better...

 

[MattyB]

"SoH evaluation:
- First, a battery management system evaluates the SoH of the battery under its management and reports it."

State of Health

Err, sorry, that tells us precisely nothing about the method used...

Parameters
As SoH does not correspond to a particular physical quality, there is no consensus in the industry on how SoH should be determined. The designer of a battery management system may use any of the following parameters (singly or in combination) to derive an arbitrary value for the SoH.

• Internal resistance / impedance / conductance
• Capacity
• Voltage[2]
• Self-discharge
• Ability to accept a charge
• Number of charge–discharge cycles

In addition, the designer of the battery management system defines an arbitrary weight for each of the parameter's contribution to the SoH value. The definition of how SoH is evaluated can be a trade secret.

 

[Tamas]

Err, sorry, that tells us precisely nothing about the method used...

Parameters
As SoH does not correspond to a particular physical quality, there is no consensus in the industry on how SoH should be determined. The designer of a battery management system may use any of the following parameters (singly or in combination) to derive an arbitrary value for the SoH.

• Internal resistance / impedance / conductance
• Capacity
• Voltage[2]
• Self-discharge
• Ability to accept a charge
• Number of charge–discharge cycles

In addition, the designer of the battery management system defines an arbitrary weight for each of the parameter's contribution to the SoH value. The definition of how SoH is evaluated can be a trade secret.

Since I'm not an electrical engineer even if I knew the exact method in use I wouldn't be better off... I get a number from the diagnostic report and I can compare it to the range I can achieve with one charge. If they correspond with each other then it's good but if not then the number in the report is off.

 

[100 Cols]

I put the question in the first post waiting for others to chime in to see if there is a real-life difference between charging methods and how fast the battery capacity goes down after a number of charging cycles...

I tried to check how my mistreated batteries are doing, but unfortunately they are not compatible with eTube, no information is available using SM-PCE1 box and a laptop with eTube (it's a rare Snakepower battery):

 

[Tamas]

I tried to check how my mistreated batteries are doing, but unfortunately they are not compatible with eTube, no information is available using SM-PCE1 box and a laptop with eTube (it's a rare Snakepower battery):

View attachment 8150

Hmmm that’s interesting... but makes sense. Third party battery and BMS.

 

[Nautonier]

Happy to report that both of my batteries are still at 100% after charging them right up to full for the last 2 months. This does not mean that I will be continuing this practice, but I'd like to see reports from other users who have done the same for longer than 2 months.

 

[Tamas]

Happy to report that both of my batteries are still at 100% after charging them right up to full for the last 2 months. This does not mean that I will be continuing this practice, but I'd like to see reports from other users who have done the same for longer than 2 months.

Awesome, how many charging cycles?

 

[Gary]

If the range drops 10% and the diagnosis will still show 99% remaining capacity then I know it's way off... it's not rocket science.

Unless you do two identical road rides in identical wind conditions dressed identically at exactly the same pace/power/cadence/gearing how on earth are you going to measure range accurately? No two rides are identical. Especially off road. Even following exactly the same route at the same pace effort/assistance is not necessarily going to be the same. Infact the rider effort is highly likely to be as much as a 10% difference between the two rides.


My battery has:
8 months use.
Over 100 rides.
One month of no use whatsoever
Been charged to full every charge.
Never been left discharged completely for more than a few hours
100% remaining charge

I may have made up one of the above starements.

Because that's not far off how much accuracy I believe this thread has.

Much like your phone. The battery should be good for at least a few years and is warrantied incase it suddenly stops holding a decent charge, I'd stop worrying about it and just ride your bike.

 

[Nautonier]

Awesome, how many charging cycles?

8 on one battery, 3 on the other.

 

[Tamas]

Unless you do two identical road rides in identical wind conditions dressed identically at exactly the same pace/power/cadence/gearing how on earth are you going to measure range accurately? No two rides are identical. Especially off road. Even following exactly the same route at the same pace effort/assistance is not necessarily going to be the same. Infact the rider effort is highly likely to be as much as a 10% difference between the two rides.


My battery has:
8 months use.
Over 100 rides.
One month of no use whatsoever
Been charged to full every charge.
Never been left discharged completely for more than a few hours
100% remaining charge

I may have made up one of the above starements.

Because that's not far off how much accuracy I believe this thread has.

Much like your phone. The battery should be good for at least a few years and is warrantied incase it suddenly stops holding a decent charge, I'd stop worrying about it and just ride your bike.

Oh really??? I always thought that all rides and the range is always the same regardless of weight, weather, road/surface conditions, rider input, assist mode, etc. Thank you for enlightening me...

Again, apart from you, nobody was talking about the accuracy of anything but a number that the BMS reported. I cannot talk for others, but I ride enough, know my bike and I have routes where I’m able to ‘test’ the range where I would notice a 10% drop in capacity.

I’m not trying to force my opinion and tell you that you should do ‘this or that’ with your battery (or how whatever). I thought we are all grownups and we can decide for ourselves what we do or don’t do but it seems it’s not the case.
I don’t know where did you get that I’m “worrying” I’m just interested in more than just riding. Is it OK with you or should I stop being interested?

 

[Gary]

No. do whatever you want.
There are folk out there who spend their lives geeking over, collecting and building bikes and never actually ride them at all and I'm absolutely fine with that too. I'm simply disputing the accuracy of your findings.

*collective "your"

 

[Tamas]

No. do whatever you want.
There are folk out there who spend their lives geeking over, collecting and building bikes and never actually ride them at all and I'm absolutely fine with that too. I'm simply disputing the accuracy of your findings.

*collective "your"

I didn't claim 'accuracy' but you can, of course, dispute it.

Regarding your projection, I'm eager to find out which category do I belong to in your expert opinion?
So far this year, I rode 5,837.69km - 3,039.72 with my ebike, and 2,797.97km with my XC and enduro bikes.
(Disclaimer - I don't have a claim on the accuracy of the Garmin Edge 1000 and Fenix 3 and the errands with my city bike are not tracked.)

 

[Deleted member 1478]

I’m really interested in the best means to manage my battery. Even a 10% attenuation in range will piss me off - the longer I can avoid that the better.

I get the impression that nobody knows the full story on the best approach to managing battery life.

So it seems odd to diss people having a fair go at putting ideas out there for discussion? I’m working out pretty quickly who the snarks are. ?

 

[Gary]

I'm eager to find out which category do I belong to in your expert opinion?

I hadn't put you in one. I don't put people into categories. Before now I had no idea what sort of mileage you did.

I get the impression that nobody knows the full story on the best approach to managing battery life.

This ^^. there are definitely good practice guidelines though

So it seems odd to diss people having a fair go at putting ideas out there for discussion? I’m working out pretty quickly who the snarks are. ?

I'm not actually dissing anyone mate.
I'm simply dis(puting) the accuracy of peoples findings.
I'll freely admit I'm cynical AF though.

 

[Tamas]

I get the impression that nobody knows the full story on the best approach to managing battery life.

Absolutely... that's why I asked in the first post so we can compare battery health (reported by the BMS without being certain about its accuracy), number of charge cycles and charging methods. Should someone care about all this? It's up to the person...

Also, I think the used market for ebikes is growing every day and it's good to be able to run a system diagnosis before purchasing one, it can save a trip to an LBS.

 

[100 Cols]

Absolutely... that's why I asked in the first post so we can compare battery health (reported by the BMS without being certain about its accuracy), number of charge cycles and charging methods. Should someone care about all this? It's up to the person...

Also, I think the used market for ebikes is growing every day and it's good to be able to run a system diagnosis before purchasing one, it can save a trip to an LBS.

Even though I carelessly charge my batteries 100% after every ride, I do understand your point and I'd also be interested in hearing/seeing battery reports from those of us who have had their bike few months already.

 

[MattyB]

I’m really interested in the best means to manage my battery. Even a 10% attenuation in range will piss me off - the longer I can avoid that the better.

I get the impression that nobody knows the full story on the best approach to managing battery life.

There are billions and billions going into battery research every year, most notably for electric cars, electric aircraft and mass storage solutions. As a result the storage and management of lithium ion batteries is very well understood by industry - don't deep discharge, don't store at elevated SOC, don't store, charge or use packs at very high or very low temperatures, don't overcharge, and don't pull current at greater than the C rating of the pack. Remember, the packs in our bikes are nothing revolutionary - they are the same in chemistry terms as the vast majority of rechargeable consumer devices bought today.

The problem is not a lack of understanding of the batteries overall, it's that the bike industry is very new to this whole space. Even though manufacturers have undoubtedly had battery experts involved in designing their packs, the information on usage and care does not seem to be filtering down into the instructions for consumers or training to mechanics in your LBS. The result is this jumbled guidance from manufacturers on battery care, different warranty terms and expected cycle lives, and general confusion amongst consumers as a result on how to care for their pack. Cynics might also suggest it is in the manufacturers interest not to teanch people how to optimally use their battery; certainly reviewing the guidance in the Levo manual online had me thinking that, so vague was the advice.