Charging methods - battery health

[Tamas]

I was thinking we could compare the effects of the charging methods on the battery health and if any particular method is better or worth the 'extra mile' to preserve the battery capacity for longer. As far as I know, the battery diagnostic is possible by the user through the app on the Levo/Brose and the Shimano systems.

Here is mine:
2 batteries, 11 months, 24 and 28 charge cycles and 99% remaining capacity on both batteries.
After rides, I charge the battery to ~70-90% and before the next ride I top it off to 100%.

 

[Nautonier]

Sorry for the newbie question, but how can one find this diagnostic information for an ebike battery? I've got 2 x Shimano batteries, but can't find a Shimano app that will give me anything like what you've displayed. Is it Android only?

 

[Tamas]

Sorry for the newbie question, but how can one find this diagnostic information for an ebike battery? I've got 2 x Shimano batteries, but can't find a Shimano app that will give me anything like what you've displayed. Is it Android only?

No, you can run diagnostics with the tablet version of the E-Tube Project app.

Tap the 'button' on the top right and tap 'Unit log aquisition':

Then on the bottom tap 'PDF' and you will be able to view and save it.

 

[Nautonier]

Tablet? You mean ipad? I can see this app in the App store, but it appears to be only for Di2??

 

[MattyB]

I was thinking we could compare the effects of the charging methods on the battery health and if any particular method is better or worth the 'extra mile' to preserve the battery capacity for longer. As far as I know, the battery diagnostic is possible by the user through the app on the Levo/Brose and the Shimano systems.

Here is mine:
2 batteries, 11 months, 24 and 28 charge cycles and 99% remaining capacity on both batteries.
After rides, I charge the battery to ~70-90% and before the next ride I top it off to 100%.

View attachment 8041 View attachment 8042

Sounds like a sound strategy to me, though would not leave the pack as high as 90% betweeen uses myself, particularly if it was not going to be ridden for a few days - 70% is fine to protect against self discharge (which is a bit of a non-issue with Li batteries anyway). It certainly aligns with generally accepted best practice for the preservation of Lithium ion batteries...

How to Prolong Lithium-based Batteries - Battery University

 

[100 Cols]

That sounds very complicated strategy, Tamas. And how on earth do you charge a battery up to 72.8% with a standard charger anyway?

Let's do some calculation:

IIRC Shimano promises 1000 charging cycles for a battery. If I'd ride 6 times a week, using full battery capacity every time, I would get 166 weeks (3 years) out of one battery. As I use two batteries, I'd be good for 6 years with these 2 batteries... but as I usually use only 2/3 of the full capacity, the battery life expectancy goes up* to 9 years. By that time I'll have no bicycle where to use those batteries anymore (not so wild guess) and hopefully the battery technology has advanced and rendered those antique (by then) batteries useless anyway.

So why would I start fuzzing with battery charging strategies? I guess I'm lazy and stupid, but when I'm back from a ride, I just swap the batteries. Fully charged in, depleted out, then start charging the depleted one. Bike is always ready for a ride, no need to _plan_ rides.

* AFAIK one charge cycle is 100%-0%-100% or e.g. 2 times 100%-50%-100%.

 

[steve_sordy]

All interesting stuff, I need to know this.

 

[Tamas]

That sounds very complicated strategy, Tamas. And how on earth do you charge a battery up to 72.8% with a standard charger anyway?

Let's do some calculation:

IIRC Shimano promises 1000 charging cycles for a battery. If I'd ride 6 times a week, using full battery capacity every time, I would get 166 weeks (3 years) out of one battery. As I use two batteries, I'd be good for 6 years with these 2 batteries... but as I usually use only 2/3 of the full capacity, the battery life expectancy goes up* to 9 years. By that time I'll have no bicycle where to use those batteries anymore (not so wild guess) and hopefully the battery technology has advanced and rendered those antique (by then) batteries useless anyway.

So why would I start fuzzing with battery charging strategies? I guess I'm lazy and stupid, but when I'm back from a ride, I just swap the batteries. Fully charged in, depleted out, then start charging the depleted one. Bike is always ready for a ride, no need to _plan_ rides.

* AFAIK one charge cycle is 100%-0%-100% or e.g. 2 times 100%-50%-100%.

I don't see it as 'complicated'. I don't charge it fully after rides that's all... From the 'end of ride' charge of the battery, I can guess how long I need to charge it to be somewhere between 70-90%. After a while, the guesswork gets more accurate and before the next ride I top it off that's all.
Obviously, if I could ride six days a week then absolutely no need for charging strategy but sometimes I cannot ride for a week or two and I don't want to store the battery empty or fully charged.
Yes, Shimano promises ~1000 charge cycles and one cycle is 0 to 100% (although not exactly but close). The charging method will affect how much of the original capacity the battery can hold after a number of charging cycles. According to Shimano, 10% drop in a year is normal, and for some of us, the changing capacity is noticeable. Trying to care about it/preserve it is not mandatory for anybody it's a choice.
Nobody told you that you need to have any battery charging strategies you do whatever you want to do and suits your needs...

 

[paquo]

That sounds very complicated strategy, Tamas. And how on earth do you charge a battery up to 72.8% with a standard charger anyway?

Let's do some calculation:

IIRC Shimano promises 1000 charging cycles for a battery. If I'd ride 6 times a week, using full battery capacity every time, I would get 166 weeks (3 years) out of one battery. As I use two batteries, I'd be good for 6 years with these 2 batteries... but as I usually use only 2/3 of the full capacity, the battery life expectancy goes up* to 9 years. By that time I'll have no bicycle where to use those batteries anymore (not so wild guess) and hopefully the battery technology has advanced and rendered those antique (by then) batteries useless anyway.

So why would I start fuzzing with battery charging strategies? I guess I'm lazy and stupid, but when I'm back from a ride, I just swap the batteries. Fully charged in, depleted out, then start charging the depleted one. Bike is always ready for a ride, no need to _plan_ rides.

* AFAIK one charge cycle is 100%-0%-100% or e.g. 2 times 100%-50%-100%.

I think a battery has a life cycle that is effected by both usage and time. Time there is nothing you can do about. Basic practice is you store a battery in cool temps 75% + - state of charge. Nothing complicated about that.

 

[100 Cols]

Basic practice is you store a battery in cool temps 75% + - state of charge. Nothing complicated about that.

Yeah, it's all subjective. I like simplicity and for me that's complicated, because it's guesswork (how to reach 75%) and I would need to plan and prepare for the next ride, recharge the battery two times.

 

[MattyB]

I think a battery has a life cycle that is effected by both usage and time. Time there is nothing you can do about. Basic practice is you store a battery in cool temps 75% + - state of charge. Nothing complicated about that.

Yep, this is defintiely true. It's why (unless you do regular rides of >1 battery duration, which in the Focus I guess is more likely) it's probably a better bet to run your initial battery into the ground then buy a replacement, rather than buying two and rotating them between rides.

 

[MattyB]

Yeah, it's all subjective. I like simplicity and for me that's complicated, because it's guesswork (how to reach 75%) and I would need to plan and prepare for the next ride, recharge the battery two times.

TBH as long as you are not planning on leaving the battery a very long time without use (i.e. >3 months) anything between 40-80% is ok. It's not leaving it at 90-100% that is the key.

 

[Tamas]

Yep, this is defintiely true. It's why (unless you do regular rides of >1 battery duration, which in the Focus I guess is more likely) it's probably a better bet to run your initial battery into the ground then buy a replacement, rather than buying two and rotating them between rides.

If one battery is enough then no point of having two. For some of us two is necessary for longer rides and if you have two, I think it's better to rotate them.

 

[paquo]

I like simplicity and for me that's complicated, because it's guesswork (how to reach 75%).

I take for granted the specialized mission control ap that shows battery charge. I tend to use a bit less than 50% per ride on the 700 w battery so it takes a few hours on the charger on the morning of the next ride

 

[Jeff McD]

Someone speculated in an earlier thread that the specialized battery management software probably prevents charging the battery greater than 80% when registering a full charge, in order to prevent overcharging. That would render this discussion entirely academic.
Does anyone have any contact with specialized to verify this? We need to know how close to 100% the battery actually gets charged when fully charged. Most of my rides also only use between 40% to 80% of my 2018 levo batteries capacity. Never know how long my next ride will last, so I have been charging it fully right after the ride. Would you like to start managing this better as described above if the battery management software does truly charge the battery back to 100% versus 80%.
Rob, would you know anybody at Berkshire who could clarify this?

 

[Mattwilko92]

With lithium ion batteries in any application you’re limited to what you can do to prolong the life. I would quite simply make sure they don’t get too hot or cold and if being stored for a long period of time (couple of months) leave them around 40%-60%.

Leave the rest to the built in battery management software. Don’t worry about fully discharging the batteries to 10% or so as they fully recover.

 

[Deleted member 1478]

TBH as long as you are not planning on leaving the battery a very long time without use (i.e. >3 months) anything between 40-80% is ok. It's not leaving it at 90-100% that is the key.

This seems reasonable. It’s easy to put the charger on a timer the night before a ride so that it’s fully charged in the wee hours ready for a ride the next day.

I’m also storing mine in a sealed bag in the fridge as the garage often gets well over 30*C here in Aussie in the summer. Evidently the chemistry prefers cooler temps.

 

[Markymark]

As another hobby of mine is flying quads I use Lithium Polymer (Li-Po) in them.
Now 4.2 volts per cell is considered a fully charged cell and 3.0v fully discharged and are sold describing a nominal voltage of 3.7 volts. So a 1s battery (1 cell) is 3.7v, 2s 7.4v, 3s 11.1 etc.
Now for long term storage we usually charge them to 3.85v per cell.
A quick search reveals that Lithium ion batteries should be stored at 40% charged state at around 60 degrees f.
Now my model batteries can be damaged if they are discharged to deeply so we normally fly to around 3.3v per cell. we use on board voltage monitoring which is displayed in our googles and some have audible warning systems as we usually have no protection against flying beyond this threshold.
I have a computer controlled charger for charging these batteries. You plug the main power lead on the battery to the charger then what's called the balance lead on the battery into the charger as well. This monitors the voltage of each cell and automatically 'balances' each cell to prevent any possible overcharging of one cell which could result in an explosion and fire. I usually find when charging is complete each cell is within .01 of a volt.
I guess the E-bike manufactures have an auto protection built into the batteries to prevent batteries from being deep discharged and presume that a battery is made up of individual cells and that the chargers supplied monitor cell voltage as well.
I still keep to my safety rules when charging my battery (even though I have only had an EMTB for 4 weeks) i.e. don't leave it unattended and I check to see if it's getting hot while charging.
Sorry this is a bit off topic and could be talking out of my behind when it come to EMTB batteries but most advice I've seen is store fully charged which goes against the grain for me but until I hear different I do leave mine fully charged.
I should also add that long term storage is usually if you aren't going to use them for a few weeks, so if you go out every week there shouldn't be any issues.
Cheers, Mark

 

[MattyB]

As another hobby of mine is flying quads I use Lithium Polymer (Li-Po) in them.
Now 4.2 volts per cell is considered a fully charged cell and 3.0v fully discharged and are sold describing a nominal voltage of 3.7 volts. So a 1s battery (1 cell) is 3.7v, 2s 7.4v, 3s 11.1 etc.
Now for long term storage we usually charge them to 3.85v per cell.
A quick search reveals that Lithium ion batteries should be stored at 40% charged state at around 60 degrees f.
Now my model batteries can be damaged if they are discharged to deeply so we normally fly to around 3.3v per cell. we use on board voltage monitoring which is displayed in our googles and some have audible warning systems as we usually have no protection against flying beyond this threshold.
I have a computer controlled charger for charging these batteries. You plug the main power lead on the battery to the charger then what's called the balance lead on the battery into the charger as well. This monitors the voltage of each cell and automatically 'balances' each cell to prevent any possible overcharging of one cell which could result in an explosion and fire. I usually find when charging is complete each cell is within .01 of a volt.
I guess the E-bike manufactures have an auto protection built into the batteries to prevent batteries from being deep discharged and presume that a battery is made up of individual cells and that the chargers supplied monitor cell voltage as well.
I still keep to my safety rules when charging my battery (even though I have only had an EMTB for 4 weeks) i.e. don't leave it unattended and I check to see if it's getting hot while charging.
Sorry this is a bit off topic and could be talking out of my behind when it come to EMTB batteries but most advice I've seen is store fully charged which goes against the grain for me but until I hear different I do leave mine fully charged.
I should also add that long term storage is usually if you aren't going to use them for a few weeks, so if you go out every week there shouldn't be any issues.
Cheers, Mark

Excellent post, couldn’t agree more. I keep meaning to put a voltmeter across the terminals of my Dad’s Bosch battery to see what the “fully” charged and fully discharged voltages are so we can work out what values the BMS uses to manage the battery health. It may be that the batteries are automatically disconnected from the contacts when not connected though to prevent shorts. Anyone got a voltmeter who can have a go?

 

[Levo Lution]

If charging batteries the same (proper way) which battery will last more charge cycles shimano or brose? Both 500wh

 

[Nautonier]

Struggling a bit with finding out my battery info on the Shimano E - TUBE PROJECT app. To connect using bluetooth, it's telling me to "Set the unit on the bicycle to bluetooth LE connection mode". I'm not sure how to do that, there are no settings relating to bluetooth on the head unit. Any help greatly appreciated, this is all new to me and I would like to see how much damage I've already done to my batteries by often accidentally leaving them at 100% charge.

Also, I don't suppose there is any easy way to 'discharge' the batteries if they are overcharged other than a few fast boost laps (dragging the brakes) around the block?

 

[Gary]

E-tube App connects via the bluetooth LE setting on the bike's display. press and hold the display button and cycle up and down through the menu with the shifter pressing the button to enter. Open the App and hopefully the two will connect when you tap on E8000 when it's recognised by your phone.
E-Tube App doesn't give battery diagnosis. It allows you update firmware, alter assist settings in boost and trail, choose display settings and information shown and other minor things like enabling lights.

I just charge mine back to full as soon as I'm home after pretty much every ride of a half decent length (more than just popping a couple of miles to the shop and back etc . Longest it'll ever be left fully charged and unridden for about 3 days tops. if that damages the cells i have a 2yr battery warranty to cover it. Shimano has a 5 light battery charge meter so it's impossible to tell what % it's charged to anyway unless you keep checking it while it charges and life's too short for that. plus it's kinda annoying heading out at short notice knowing you don't have a full charge should you want to use it all.

Riding around in boost with your brakes on is crazy talk. for one thing you'll risk glazing the pads. Using the overcharged battery excuse to get out for a ride sounds fair enough though.

 

[Tamas]

E-Tube App doesn't give battery diagnosis.

If that damages the cells i have a 2yr battery warranty to cover it.

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...

 

[highpeakrider]

E-tube App connects via the bluetooth LE setting on the bike's display. press and hold the display button and cycle up and down through the menu with the shifter pressing the button to enter. Open the App and hopefully the two will connect when you tap on E8000 when it's recognised by your phone.
E-Tube App doesn't give battery diagnosis. It allows you update firmware, alter assist settings in boost and trail, choose display settings and information shown and other minor things like enabling lights.

I just charge mine back to full as soon as I'm home after pretty much every ride of a half decent length (more than just popping a couple of miles to the shop and back etc . Longest it'll ever be left fully charged and unridden for about 3 days tops. if that damages the cells i have a 2yr battery warranty to cover it. Shimano has a 5 light battery charge meter so it's impossible to tell what % it's charged to anyway unless you keep checking it while it charges and life's too short for that. plus it's kinda annoying heading out at short notice knowing you don't have a full charge should you want to use it all.

Riding around in boost with your brakes on is crazy talk. for one thing you'll risk glazing the pads. Using the overcharged battery excuse to get out for a ride sounds fair enough though.

I just do the same, ride and charge.
I’m not about to get anal about it, it’s a bike, this is getting like an Apple forum with the iPhone boys.

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?

 

[Tamas]

If charging batteries the same (proper way) which battery will last more charge cycles shimano or brose? Both 500wh

I guess they will be pretty much the same as they all use good quality cells.
I'm waiting if someone else will post 'charge cycles/battery health and charging method' so we could see if there is any difference. Specialized MC and Shimano E-Tube (tablet) app give this info.

 

[MattyB]

If charging batteries the same (proper way) which battery will last more charge cycles shimano or brose? Both 500wh

Guarantee length may be different (that’s more a marketing decision as to the % of packs they will price in to replace under warranty), but they fundamentally use the same battery chemistry and cells. Unless one manufacturer has done a terrible job of designing the BMS and cooling they should be very similar in terms of cycle life.

 

[Tamas]

I just do the same, ride and charge.
I’m not about to get anal about it, it’s a bike, this is getting like an Apple forum with the iPhone boys.

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?

Some of us are only interested in riding and some of us are interested in technical aspects too. I don't see the slightest problem with either...

Battery capacity significantly drops in the cold and it's up to you if you want to cover it or not.

 

[highpeakrider]

Some of us are only interested in riding and some of us are interested in technical aspects too. I don't see the slightest problem with either...

Battery capacity significantly drops in the cold and it's up to you if you want to cover it or not.

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.

 

[Markymark]

I just do the same, ride and charge.
I’m not about to get anal about it, it’s a bike, this is getting like an Apple forum with the iPhone boys.

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?

Just keep the battery indoors. All batteries suffer in the cold.

 

[R120]

The range suffers in cold weather - you will notice if you are riding in low temps the range isnt as good.