Do's and Don'ts for e-bike battery care. What do you do to keep your battery performing at its best?

[RJUK]

Whatever the reason, the point was that this is a 4 year old battery that has never had that 80% option, is a small one so has frequently been charged to 100% but 170 cycles and 2800+ miles in it’s still 100% healthy.

It’s just been used to suit me rather than the other way around.

The motor sounds like a bag of spanners though, motors are what concern me! I wonder if leaving it turned off wherever possible on a ride, only using Eco and not ever washing the bike would help? Imagine that!

But it's not still 100% healthy though. That number is a lie. Even if you had not used the battery at all and just stored it at the perfect SOC in a fridge, it would still have lost some capacity. Lithium batteries that don't degrade whatsoever just don't exist.

You can use your bike how you like. Dunk it in a pond to wash it if that's convenient for you and leave it switched on 24/7., but this thread is about how to best look after the battery. Charging it to 100% and storing it full is not the best way to look after it, regardless of anecdotal evidence.

 

[Tooks]

But it's not still 100% healthy though. That number is a lie. Even if you had not used the battery at all and just stored it at the perfect SOC in a fridge, it would still have lost some capacity. Lithium batteries that don't degrade whatsoever just don't exist.

You can use your bike how you like. Dunk it in a pond to wash it if that's convenient for you and leave it switched on 24/7., but this thread is about how to best look after the battery. Charging it to 100% and storing it full is not the best way to look after it, regardless of anecdotal evidence.

For goodness sake…

It is 100% for the purposes of my ability to use the bike as it was designed. It has the same range visible to me as it always did, of course it will have degraded, but if Specialized are hiding that degradation from me in the way of a decent BMS, why do I care? It doesn’t get visibly any bigger to you because you’ve been afraid to use it below 20% or above 80%.

You don’t, unfortunately, have the ultimate say on what gets posted on a given thread, I’m free to interject things I think relevant to the topic.

You’re relying on a lot of anecdotal ‘evidence’ and research, battery tech is moving on all the time, the internet myths and legend around it unfortunately don’t. You’re also scaremongering unnecessarily, in my humble opinion.

If you don’t want a reasoned range of opinions on the topic, please start your own forum and ban me from it.

 

[RJUK]

For goodness sake…

It is 100% for the purposes of my ability to use the bike as it was designed. It has the same range visible to me as it always did, of course it will have degraded, but if Specialized are hiding that degradation from me in the way of a decent BMS, why do I care? It doesn’t get visibly any bigger to you because you’ve been afraid to use it below 20% or above 80%.

You don’t, unfortunately, have the ultimate say on what gets posted on a given thread, I’m free to interject things I think relevant to the topic.

You’re relying on a lot of anecdotal ‘evidence’ and research, battery tech is moving on all the time, the internet myths and legend around it unfortunately don’t. You’re also scaremongering unnecessarily, in my humble opinion.

If you don’t want a reasoned range of opinions on the topic, please start your own forum and ban me from it.

OK, just change the meaning of 100% to suit you then I guess. And the purpose of the thread isn't to give information on what you care about, it's on how best to look after the battery. Nobody is forcing anyone to do any of this stuff, it's up to the individual, but acting like because your BMS shows 100% that means there's no degradation is spreading false information. I'm not relying on any anecdotal evidence, only what scientific testing has shown and what the battery manufacturers advise.

I'm also not scaremongering, facts are facts. If the degradation concerns you, then you can follow the ways to recude them. If they don't bother you, then why even open the thread?! You've clearly decided before even opening it that you don't care what it says and will carry on doing what you were already doing regardless...

And I'm not trying to have ultimate say over what's posted, but like you're disagreeing with me, I can disagree with you. Or is it only a debate if just you get to speak?

Sadly, the facts around lithium batteries don't take opinions into account. You can have an opinion on whether it's worth following battery care, but that doesn't change what will happen with the battery if you don't.

 

[TimC7]

For goodness sake…

It is 100% for the purposes of my ability to use the bike as it was designed. It has the same range visible to me as it always did, of course it will have degraded, but if Specialized are hiding that degradation from me in the way of a decent BMS, why do I care? It doesn’t get visibly any bigger to you because you’ve been afraid to use it below 20% or above 80%..

100% means it's fully charged, anything else is pretty irrelevant. Just like the rest of the bike won't be like new - brake fluid, chain/gears, suspension, bearings - all used but it still works OK for most of us so 100% ready to go until things need replacing or break.

 

[Tooks]

OK, just change the meaning of 100% to suit you then I guess. And the purpose of the thread isn't to give information on what you care about, it's on how best to look after the battery. Nobody is forcing anyone to do any of this stuff, it's up to the individual, but acting like because your BMS shows 100% that means there's no degradation is spreading false information. I'm not relying on any anecdotal evidence, only what scientific testing has shown and what the battery manufacturers advise.

I'm also not scaremongering, facts are facts. If the degradation concerns you, then you can follow the ways to recude them. If they don't bother you, then why even open the thread?! You've clearly decided before even opening it that you don't care what it says and will carry on doing what you were already doing regardless...

And I'm not trying to have ultimate say over what's posted, but like you're disagreeing with me, I can disagree with you. Or is it only a debate if just you get to speak?

Sadly, the facts around lithium batteries don't take opinions into account. You can have an opinion on whether it's worth following battery care, but that doesn't change what will happen with the battery if you don't.

I have never said that 100% in the BMS means no degradation. Show me where?

The discussion, such as it is, is veering between straight chemical battery degradation and available battery capacity for the given application, which in this case is powering a motor to assist your pedalling. The two things can be quite different.

There is not a jot of actual evidence that a battery treated differently to mine would be showing any difference with regard to its state of health or usable intended capacity at 4 years old. I’ve just used it, given it no special treatment. What you and others keep repeating is better described as good practice, as far as most people understand batteries anyway.

If people want to turn their 750Wh into an effective 450Wh by never using 40% of it, (not below 20%, not above 80% has been suggested) then crack on, up to them. Not really any need for debate, but It might not last any longer, you won’t see any more usable capacity than that the manufacturer allows you to see, and it’s probably unnecessary.

From just about page 1 of this thread there was no disagreement that lithium batteries degrade with use and age, a few of us have merely suggested that it might not matter that much given the vagaries of how it’s attached to a pedal assist system where the range you get on each charge cycle depends as much on you as the battery.

 

[RJUK]

100% means it's fully charged, anything else is pretty irrelevant. Just like the rest of the bike won't be like new - brake fluid, chain/gears, suspension, bearings - all used but it still works OK for most of us so 100% ready to go until things need replacing or break.

Sure, but context is important. The assertion being made was that after treating the battery a certain way after a few years was still showing 100% so the battery had not suffered any degradation whatsoever.

The thread is about how to best treat a battery to extend longevity. In this regard, there are clear "do's and don'ts" as the thread title would put it.

Yes everything degrades, but this thread is about what to do with the battery to reduce that.

 

[Tooks]

100% means it's fully charged, anything else is pretty irrelevant. Just like the rest of the bike won't be like new - brake fluid, chain/gears, suspension, bearings - all used but it still works OK for most of us so 100% ready to go until things need replacing or break.

Battery charge percentage and battery health percentage mean two different things, that’s why they’re both displayed in the specialized app.

Battery state of charge is not the same as available battery capacity, which is what is being referred to by battery health.

 

[Tooks]

Sure, but context is important. The assertion being made was that after treating the battery a certain way after a few years was still showing 100% so the battery had not suffered any degradation whatsoever.

The thread is about how to best treat a battery to extend longevity. In this regard, there are clear "do's and don'ts" as the thread title would put it.

Yes everything degrades, but this thread is about what to do with the battery to reduce that.

That is not what was being asserted at all.

Please stop being so disingenuous with your posting.

 

[RJUK]

I have never said that 100% in the BMS means no degradation. Show me where?

The discussion, such as it is, is veering between straight chemical battery degradation and available battery capacity for the given application, which in this case is powering a motor to assist your pedalling. The two things can be quite different.

There is not a jot of actual evidence that a battery treated differently to mine would be showing any difference with regard to its state of health or usable intended capacity at 4 years old. I’ve just used it, given it no special treatment. What you and others keep repeating is better described as good practice, as far as most people understand batteries anyway.

If people want to turn their 750Wh into an effective 450Wh by never using 40% of it, (not below 20%, not above 80% has been suggested) then crack on, up to them. Not really any need for debate, but It might not last any longer, you won’t see any more usable capacity than that the manufacturer allows you to see, and it’s probably unnecessary.

From just about page 1 of this thread there was no disagreement that lithium batteries degrade with use and age, a few of us have merely suggested that it might not matter that much given the vagaries of how it’s attached to a pedal assist system where the range you get on each charge cycle depends as much on you as the battery.

There is evidence though, that's the point.

There has been testing done that shows that calendar aging of lithium batteries is accelerated by both higher temperatures and higher SOC, so keeping your battery SOC lower between uses slows the aging of the battery, as does keeping it in a cooler environment. Also, shallower charge cycles will extend the life of the battery. Those are well established facts.

Now, whether that is of any concern to you, or if your mindset is "it's a tool, so I'll just use it as I wish and not worry", is fine, but it doesn't change those facts.

How much it matters in practise, I'm not sure exactly. Everyone's usage is different and battery chemistries differ, etc. And newer lithium batteries have proven to suffer less degradation than anticipated, which is great.

But, if you've come to this thread then you're probably looking for information on how to best look after your battery to keep it in as good condition as practically possible.

To that end, my simple recommendations would be to:

Store it between 30 - 40% between rides, in a cool, dry place.

Charge before you use the bike, not immediately after.

Only charge to 100% if you really need the whole battery for your ride. If you're going out for a regular ride and you know you will only use 30% of the battery, then charge it to 60 - 70% so you get back with around 30 - 40% and have spare if you need it.

If it's too much grief to do any of those, then omit as you like. It's your bike and the battery has a warranty that it will stay above a certain capacity for a certain period anyway.

But mainly, enjoy your bike!

 

[RJUK]

That is not what was being asserted at all.

Please stop being so disingenuous with your posting.

That's absolutely not what I'm doing at all.

You were arguing against my points on battery health by saying that you have ignored all of it and yours still showed 100%, what else was I supposed to infer from that?

Perhaps you should stop making wild accusations and be more clear about what you mean.

 

[Tooks]

That's absolutely not what I'm doing at all.

You were arguing against my points on battery health by saying that you have ignored all of it and yours still showed 100%, what else was I supposed to infer from that?

Perhaps you should stop making wild accusations and be more clear about what you mean.

To be clear, again, I was demonstrating that one of my own batteries in one of my own e-bikes used at my convenience rather than that of the battery is telling me that after 4 years, 170 charge cycles and 2200+ miles that it’s available capacity was 100%.

It even says that in the app screenshot;

“Maximum Capacity is a measure of battery capacity relative to when it was new. Lower capacity may result in fewer hours of usage
between charges.”

How much clearer can I be?

 

[Binhill1]

Whatever the reason, the point was that this is a 4 year old battery that has never had that 80% option, is a small one so has frequently been charged to 100% but 170 cycles and 2800+ miles in it’s still 100% healthy.

It’s just been used to suit me rather than the other way around.

The motor sounds like a bag of spanners though, motors are what concern me! I wonder if leaving it turned off wherever possible on a ride, only using Eco and not ever washing the bike would help?

Mine shows 100 health and I still get same miles so I will believe that rather than what some sparky on here is saying.

 

[RJUK]

To be clear, again, I was demonstrating that one of my own batteries in one of my own e-bikes used at my convenience rather than that of the battery is telling me that after 4 years, 170 charge cycles and 2200+ miles that it’s available capacity was 100%.

It even says that in the app screenshot;

“Maximum Capacity is a measure of battery capacity relative to when it was new. Lower capacity may result in fewer hours of usage
between charges.”

How much clearer can I be?

Right, so you're not just saying that it shows 100% SOC then, you are saying that you believe it still has full capacity? Or are you saying that the app shows that, but you know it's lying? Not really being very clear at all.

 

[RJUK]

Mine shows 100 health and I still get same miles so I will believe that rather than what somebody on here is say.

Good for you. Carry on believing that and do what you like. Not really sure why you're looking at the thread if you have no intention on changing your habits.

 

[Binhill1]

Good for you. Carry on believing that and do what you like. Not really sure why you're looking at the thread if you have no intention on changing your habits.

I do what you say actually but I think your taking it too personal. Happy charging.

 

[RJUK]

I do what you say actually but I think your taking it too personal. Happy charging.

Not really, I'm just trying to help others by sharing what I've researched. Seemingly that's frowned upon somehow. Perhaps I shouldn't have bothered.

In case anyone cares, here's a video explaining how to look after your battery and why it degrades faster at higher SOC and temperature and with deeper discharge cycles. It should answer the title of the thread, though I'm sure some will still choose not to believe it.

FWIW, I contacted Bosch and they confirmed that my 750 Powertube is an NMC battery like in the video. I suspect most ebikes are a similar chemistry, so the same things will likely apply.

 

[Stihldog]

But mainly, enjoy your bike!

^^My little brain can understand this!^^

I’m probably a chronic eMTB abuser but after 4+ years with the same bike I think I’m just lucky

Edit; oops, I didn’t mean it that way …ah man! Sry

 

[Tooks]

Right, so you're not just saying that it shows 100% SOC then, you are saying that you believe it still has full capacity? Or are you saying that the app shows that, but you know it's lying? Not really being very clear at all.

I’m saying that the battery management is telling me that it has 100% of the capacity relative to when it was new.

A typical lithium-ion battery is usually rated for at least 500 cycles, so 170 is not really a lot in the grand scheme of things, so why shouldn’t I believe it?

 

[Tooks]

In case anyone cares, here's a video explaining how to look after your battery and why it degrades faster at higher SOC and temperature and with deeper discharge cycles.

He says many things in the video, including ‘even if you do everything wrong, the battery will still last for a very very long time’ and also ‘if you need to charge to 100%, don’t worry about it’…

Electric car batteries are a rather different kettle of fish though, my current one at 100% SOC is still only 93% charged in reality, and it also has depth of discharge protection. The latter is pretty common to any e-bike battery BMS.

Maybe Specialized use an oversize pack to ensure that available capacity can be managed so it’s at 100% of the design capacity for as long as possible.

They seem to be good quality packs anyway.

 

[linkqwd]

Mine Specialized app shows me that my battery is 100% having 70 cycles, but I recently update mine battery firmware to be able to charge up to 80% and dealer said that mine battery capacity is actually 99% , also I found out that a friend of mine has his levo SL 2020 and his battery capacity in the app is also 100% but dealer's app shows that its only 90% (he neglected his battery charging and discharging, did it randomly)

Is this only specialized problem with showing wrong capacity in the app? or what is going on? why the app is lying to us.

 

[Binhill1]

I'm going to unwatch this thread now , I know what I should do regarding the 5 and a half year old battery with 10,000 miles on it.. My new year resolution will be stop trying to wind folk up on this forum. But it's the only forum I'm on and I don't really use Facebook just a few clubs I'm in . No friends on Facebook , awe I hear you say but that's how I like it. Happy cycling

 

[Tooks]

Mine Specialized app shows me that my battery is 100% having 70 cycles, but I recently update mine battery firmware to be able to charge up to 80% and dealer said that mine battery capacity is actually 99% , also I found out that a friend of mine has his levo SL 2020 and his battery capacity in the app is also 100% but dealer's app shows that its only 90% (he neglected his battery charging and discharging, did it randomly)

Is this only specialized problem with showing wrong capacity in the app? or what is going on? why the app is lying to us.

I think that’s consistent with what I’ve been talking about, ie the battery pack is ‘oversize’ to ensure that the designed and advertised capacity can be delivered for the reasonable life of the product.

Perhaps what dealers can see with their diagnostic kit is degradation of the complete pack (of which we agree there will always be some) which whilst it’s still above the advertised usable capacity is not a problem?

Who knows, but as others have said, happy cycling!

 

[Stihldog]

I'm going to unwatch this thread now , I know what I should do regarding the 5 and a half year old battery with 10,000 miles on it.. My new year resolution will be stop trying to wind folk up on this forum. But it's the only forum I'm on and I don't really use Facebook just a few clubs I'm in . No friends on Facebook , awe I hear you say but that's how I like it. Happy cycling

This ^^ winds me up! I thought I was the only one …but apparently I’m not

 

[linkqwd]

I think that’s consistent with what I’ve been talking about, ie the battery pack is ‘oversize’ to ensure that the designed and advertised capacity can be delivered for the reasonable life of the product.

Perhaps what dealers can see with their diagnostic kit is degradation of the complete pack (of which we agree there will always be some) which whilst it’s still above the advertised usable capacity is not a problem?

Who knows, but as others have said, happy cycling!

well, might be, but my friend on the SL, which still has 100% battery health in the app, says that the drop in his battery performance is actually pretty noticeable, its small 320wh battery and it wasn't enough back in the days and now its even worse at least its what he feels, no metrics on this.
Maybe those are different metrics in dealer and phone app, but actually I never seen that someone's specialized app showed less then 100% battery health, and spesh ebikes are the most common in my region.

 

[Gareth]

Store it between 30 - 40% between rides, in a cool, dry place.

Well if I am going to use it within the next week or so I’m gonna charge it to 100% That’s what I’ve been doing for years. Isn’t that what everybody does?

Charge before you use the bike, not immediately after.

Well the reason I do that is it takes over 3hrs to charge the battery. So not practical to charge just before I ride.

Only charge to 100% if you really need the whole battery for your ride.

Pretty much everytime I go out for fun I am going up and down the modes as required hopefully to get back home without running the battery flat. Would love to see 2 or 3000whr batteries, but I guess that is a long way off. If I am commuting to and from work, I’ll get three days out of a full charge, then charge to 100%.

If it's too much grief to do any of those, then omit as you like. It's your bike and the battery has a warranty that it will stay above a certain capacity for a certain period anyway.

My Cube battery is coming up on 4 years old. Unless the bike is being left for a few weeks its always been charged to 100%, run flat quite a number of times, and whilst I am not saying it hasn’t degraded, I’m not noticing much reduction in performance. I know it won’t last forever, it might fail tomorrow, but so far so good (with the battery – the motor is another story)

The one thing I have done over those years is being the battery inside during freezing cold weather.

Currently my new Mondraker is inside the house, I’m not using it much at the mo, so the battery is at 40% charge. Can’t remove the battery from the bike, so as soon as the tempertures lift she’ll be back outside with the Cube.

 

[Mikerb]

I wonder if there is a difference between battery health and battery "stamina" ( ie a bit like us older riders!!). I imagine a battery health check means all cells are at their nominal voltage.............but maybe they run out of steam a bit earlier. A form of sink test would be needed to identify the difference..... ie the degradation. A bit like putting a car on a rolling road! Maybe the LBS diagnostics has a way of doing that??

 

[TimC7]

Well if I am going to use it within the next week or so I’m gonna charge it to 100% That’s what I’ve been doing for years. Isn’t that what everybody does?

Buy a mechanical 24hr timer and charge it for the recommended time before you ride, that's what I do. Bike gets charged to 60% after a ride and stored. On the night before a ride I set the timer for 2hrs starting at 6am (5hrs is a full charge, so to add another 40% needs 2hrs).

 

[vikino1]

I use a smart plug.

 

[Stihldog]

I use a smart plug.

Do you mean a Smart receptacle? (120v) Wifi or phone controlled?

I’ve installed several receptacles with usb and usb-c around the house. I’ve never tried a smart plug/receptacle for use as a timer.

 

[Gareth]

Buy a mechanical 24hr timer and charge it for the recommended time before you ride, that's what I do. Bike gets charged to 60% after a ride and stored. On the night before a ride I set the timer for 2hrs starting at 6am (5hrs is a full charge, so to add another 40% needs 2hrs).

Naw, if I’ve used it and I know I’m gonna use it in the next week or so, I’ll just charge to 100%. Doesn't seem to do any harm at all.

I think folks are over thinking this.