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

billium

Member
Jul 10, 2022
107
93
Sussex
Awesome suggestion! @billium Can you share more details about the "smart plug" you're using? I'm also very Interested in trying this. Tired of forgetting that I left my battery on the charger and need to pull the plug! ;)

Amazon sells smart plugs for under a tenner

You just add it in as another device to your Alexa system - super easy.
Once done, you can immediately control it with ' Alexa, turn on first plug' ( first plug is the default name).
Now you can control the power to whatever is plugged in to it.

To automate for a bike, you need to open up the Alexa app on your phone and create 'routines' which are list of commands that are triggered by voice command or time of day.

sample to charge bike for 2 hrs

Name: charge bike 2 hrs
When you say: Alexa charge bike for two hours
Alexa will:
say ok waiting 15 minutes
wait 15 minutes
first plug power on
wait 2 hours
first plug power off
wait 1 minute
first plug power off ( done twice to make sure charger does turn off)
say bike charge finished

The app will allow you to duplicate the above routine so make copies and edit them for one hour, 3 hrs etc


The top-up is a little tricker because you cannot voice command a routine to start at a certain time but it can be done. Here is how.

Create a scheduled routine
name: sched topup bike
When its 4am , every day
Alexa will:
first plug power on
wait 4 hours
first plug power off
wait 1 minute
first plug power off ( done twice to make sure charger does turn off)
say bike topped up
Alexa, disable sched topup bike ( choose custom action)

The last command is the sneaky bit - The routine is set to run every day but in the last step it disables itself ( so it only runs once)


Finally you create a voice routine that enables the above

New voice routine
name: topup bike
When you say: Alexa topup bike
Alexa will:
Alexa, Enable sched topup bike ( choose custom action)
say: Bike will charge at 4am for four hours


The app makes the above pretty easy to do but feel free to DM me if you get stuck
 

billium

Member
Jul 10, 2022
107
93
Sussex
Wow! that's great, thanks @billium for the detailed instructions. (y)
Couple more notes
1. Alexa does not understand the contents of a command so you cannot just say Alexa charge bike for 63 minutes unless you have a routine with that exact phrase. That is why you have to have multiple routines for the one hour, two hours etc

2. when testing, edit the times to be convenient - eg set the 2 hour wait time to be 5 minutes and the 4am start to be 30 minutes from now. Once comfortable you have it working well then edit back in the real times
 
Since these Smart power plugs connect to your home LAN via WiFi, I presume you could also use your Android phone and app to control the plug, configure a few charging profiles, monitor progress, right?

I don't have Alexa at home... yet :( Have you tried using a smartphone to control these smartplugs by chance?
 
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billium

Member
Jul 10, 2022
107
93
Sussex
Since these Smart power plugs connect to your home LAN via WiFi, I presume you could also use your Android phone and app to control the plug, configure a few charging profiles, monitor progress, right?

I don't have Alexa at home... yet :( Have you tried using a smartphone to control these smartplugs by chance?
Yes you can monitor progress from the app but no sure why you would want to once the routines are set up.
Your phone can be used to issue voice commands so you don't need to buy an Echo dot too but they are often on sale for silly prices.
Just get home, plug the unpowered charger into the bike and speak the command Alexa, charge bike for 2 hours.
Having an Echo I just speak it when I walk into my kitchen. You would have to open up the Alexa App on your phone and then speak into the phone.
That's it!
 

billium

Member
Jul 10, 2022
107
93
Sussex
Ooof. No Alexa for me, thanks. I’m not fond of the ITSEC issues endemic to “smart” home devices. And, yes, I keep Siri shut off on my Apple products, as well.
Cheap Chinese cameras are generally not secure at all so yes be skeptical of allowing such Hardware into your home

But having written a Alexa skill for an IOT device, I can say that Amazon are at the secure end of the spectrum for IOT and their traffic is monitored by so many people that any funny business would be discovered very quickly. I would not worry about a smart plug.
 

IndigoUnicorn

E*POWAH Master
Sep 17, 2020
234
1,074
Las Cruces, NM
Cheap Chinese cameras are generally not secure at all so yes be skeptical of allowing such Hardware into your home

But having written a Alexa skill for an IOT device, I can say that Amazon are at the secure end of the spectrum for IOT and their traffic is monitored by so many people that any funny business would be discovered very quickly. I would not worry about a smart plug.

My partner is ITSEC at NASA here in New Mexico, and I formerly worked there.

Such tech, while monitored enough to perhaps keep most haXors out, is still not secure from Amazon itself and Bezos’ fuckery.
 
I saw this interesting MBR article "how to care for your e-bike battery" and was surprised to read that shimano guarantees a remaining capacity of 60% after 1,000 full charge cycles, while bosch guarantees 60% capacity after 500 full charge cycles.

I'm puzzled about these numbers of "usable" cycles. Not sure what it means practically for folks who intend to keep their bikes long after the 2-3 year warranty period. How "unusable" becomes the battery after exceeding the manufacturer number of usable cycles?

For a bosch battery, 500 charging cycles doesn't seem much :(

From your experience, how many useful cycles can you really expect to get out of a battery before it becomes unusable and must be replaced?

Related to this, how can you check how many cycles the battery has gone through?
 
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Alexbn921

Well-known member
Sep 27, 2021
545
511
East Bay CA
A cycle is 100% of the batteries capacity. If you go for 4 rides and use 25% or 2 rides and use 50% each = 1 cycle.

Specialized has it in the app.

Batteries wear out continuously. Every day they get worse by a small amount. It's way to slow for a user to perceive, until it's pretty bad and you can't do that extra trail you used to. The draw from an ebike is very low so you don't get a significant voltage drop that tells you it's got less power.

From a functional perspective you only loose capacity. When the battery is very low it can trigger low voltage cut if you try turbo too.

A well cared for battery should last at least 500 cycles before it feels bad.

Plug it in when you get home and let it sit at 100% should last maybe 50-200 (basically the 2 year warranty) depending on temperature and if it was drained to 0% and limped home. This assumes that it's used almost every day. It could get 0 cycles stored very hot at full charge for a year and not used.
 

Stoneilove

Active member
Jan 27, 2023
144
245
England
What is worse for the battery heat or cold?
I ask because towards the end of the year i will be storing my bike in a secure shed for around 3-5 months whilst i go away traveling so basically most of winter, the bike will have to cope with cold temps ( Based in Gloucestershire UK ).
Is this likely to hurt the battery and is there anything i can do to minimise the chances of coming back to a knackered battery?
 

Alexbn921

Well-known member
Sep 27, 2021
545
511
East Bay CA
What is worse for the battery heat or cold?
I ask because towards the end of the year i will be storing my bike in a secure shed for around 3-5 months whilst i go away traveling so basically most of winter, the bike will have to cope with cold temps ( Based in Gloucestershire UK ).
Is this likely to hurt the battery and is there anything i can do to minimise the chances of coming back to a knackered battery?
For performance cold, but it doesn't really degrade the battery.

Heat kills batteries fast.
 

Stoneilove

Active member
Jan 27, 2023
144
245
England
I agree mostly.. The real answer depends on battery chemistry so you need to find the specs for your battery.
Also even though it may be safe to store a battery about 0C never charge a very cold battery - let it warm up first.
Thanks mate 👍
 
A well cared for battery should last at least 500 cycles before it feels bad.

Plug it in when you get home and let it sit at 100% should last maybe 50-200 (basically the 2 year warranty) depending on temperature and if it was drained to 0% and limped home.
Thanks @Alexbn921 Very helpful to get some idea about what you can expect from your battery in number of cycles depending on how well (or badly) you treat your battery.

Along the same lines, I found the graph below showing that a battery's life with 500 useful cycles can be reduced to half by overcharging. But on the other hand, undercharging to 80% could increase the battery's life up to three times. I think this is significant.

batterycycles.png
 
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Growmac

Well-known member
Dec 4, 2020
384
450
Wilts, UK
From your experience, how many useful cycles can you really expect to get out of a battery before it becomes unusable and must be replaced?
I had a Shimano battery that was at 83% health after 60 cycles. The result was a battery that died if you put any serious load on it when it was below about 30% charge, and the range was probably 20% down, much more than that if you count the load issues causing it to cut out. Not great.

I don't think that's typical. That particular Shimano battery was very problematic, and there are long threads about people having issues with it and hypothesising why.
 

Paulquattro

E*POWAH Elite
May 7, 2020
2,324
1,294
The Darkside
For a bosch battery, 500 charging cycles doesn't seem much :(
If you think about it taking 50miles of assistance as an average say 625wh battery range that equates to 25,000 miles of assistance ie motor on so in push bike terms thats a fair bike ride (y)




Bosch actually guarantees their batteries for 2 years or 500 charge cycles (whichever comes first). This doesn’t mean your battery will pack up after 2 years and 1 day. In fact, Bosch themselves state that the battery should be good for around 10 years or 1500 full charge cycles. After 1500 cycles the battery will still work, but any battery will age over time so it will start to lose capacity and therefore not power your electric bike as far.
 
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randycpu

Member
Nov 15, 2018
103
45
Silicon Valley, USA
I tested the voltages that the stock Specialized BMS would allow and it's 4.2v per cell or 100% max charge. It's zero is also 0%.

The BMS does not save you and these batteries are not managed in any meaningful way. They are balanced charged and at least that is good.

The cells used, should last 10 years at a 100 cycles per year to 80% capacity.

The stock battery health app report is USELESS. It's just like the temperature gauge in your car. Look its right where it needs to be, but no real numbers.

Most people abuse there batteries and change bikes every 2 years so it doesn't matter. I love all the options of clueless users that have never researched or managed batteries that "it's okay to just keep it on the charger at 100%". Bullshit and you don't know what your talking about.
What is the per-cell voltage for 0% on the Specialized BMS? Likely 2.9V or 3.0...
 
Bosch actually guarantees their batteries for 2 years or 500 charge cycles (whichever comes first). This doesn’t mean your battery will pack up after 2 years and 1 day. In fact, Bosch themselves state that the battery should be good for around 10 years or 1500 full charge cycles
1500 full charge cycles, that's good to hear! This probably assumes the battery was well maintained and given optimal care over the years ;)
 
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Born2ski691

New Member
May 2, 2023
14
7
United States
Is any of this based on science?

I ride mine, sometimes to flat, I charge it to 100% and keep it that way.
They get charged on and off the bike in the cave. (so not warm, not cold)

All is good.

There is a lot of scare mongering around bike batteries as there is in the car world with electric cars. They're pretty robust things and can be treated pretty poorly and still perform to a good standard. Take it all with a pinch of salt from so called experts, unless they have science to back it up, I'll keep, keeping on.
Yea… as a guy who’s got 10 high power LiPo powered RC cars and 6 450 size or larger RC helicopters, I’ve got some LiPo battery experience. Oh, I’m in the robotics field too…

All that qualification aside, I agree. Take some random internet strangers thoughts with large grains of salt. I disagree with at least a couple of the earlier comments, but I don’t have data to support conclusions for any specific emtb battery setup.

What’s commonly known with lipos is:
Store 66% or so
Never charge or discharge a better that’s hot ( recently used/ charged)
Fast charging causes more heat so it’s a bit of a degrading thing.
Dispose of in a bucket of salt water… google videos of people exploding LiPo batteries if you’re inclined.
LiPo has no “memory effect” like the old NiCad’s.
If a LiPo hits about 3.6 volts, it dies suddenly, so don’t over discharge your batteries (bmw today does a pretty good job of managing that), but if you store them at 2%, they WILL. SLOWLY DISCHARGE and become dead.

And for god sake don’t drive a nail through a charges pack! 🔥

Ps, a good read…. What The Heli Is New?
 
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Alexbn921

Well-known member
Sep 27, 2021
545
511
East Bay CA
Bigger packs with max current draw of 1c can safely be run down to 3.3 and even lower when reduced to .5c near the end.

High draw rc I stop at 3.6-3.7 under load. No need to fry a battery, when I have several more waiting.
 

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