Charging question - don't overcharge?

[Camasonian]

I'm a new owner of a Turbo Vado 5.0

One thing that the bike shop clerk told me is that one gets the longest battery life if one keeps the charge between 20% and 80% or in other words, take it off the charger when you get to 80%.

I found this advice surprising because so many battery powered items these days have sophisticated circuitry to prevent overcharging and you can usually just leave an item on the charger and it will be fine. I'm looking for specific charging instructions in the manual and haven't found this specific information. The manual just says charge until the green light says "charging complete" but doesn't warn against leaving it on the charger past that point.

So what is the correct answer regarding charging these things? Do you just leave it on the charger overnight and get a full charge? Or do you try to manage the charging time to keep it at 80%?

 

[Stefan Mikes]

The answer is very simple:

• You might be paranoiac about the battery health and keep the charge between 20 and 80% and ride nowhere, or
• Use the battery with no fear, charging it to 100% and discharging down to 5% and enjoy long rides.

Yes, using the battery 100-5% shortens its life. Who cares? Not I.

P.S. Of course, the quality batteries as the ones from Specialized are protected against overcharging. It is even possible to charge the already charged battery to balance the cells. There is one question: Is the battery longevity or riding more important to you?

 

[theemartymac]

As Stefan has stated, it's pretty well established now that leaving 'reputable' products like yours on a good smart charger won't overcharge, and they should balance the cells on their own, but the 20-80% advice is also valid for a different reason. The chemical composition in lithium batteries degrades faster the higher the state of charge. So you might see a 'slight decrease' in life if you always keep it charged to 100%. General rule of thumb however, backed up by most manufacturers and builders you'll see here on this site is don't sweat the numbers for normal summer use, but try and store it comfortably below that 80% mark for extended periods or the off season to avoid unnecessarily shortening your battery life. If you really want to try and pull 8-10 years of life out of the battery, careful charging can help, including not charging the battery too fast, when it is too hot (or frozen) etc., but the average user generally just needs to avoid extremes, and use proper brand-name or trusted products.

One secondary consideration is that rare lithium battery fires from cheap ebike batteries can be quite dangerous. Most definitely a bigger concern with cheap knock-off and low end batteries, but many folks don't like to leave batteries on the charger if they can't monitor them. For example, I don't go to sleep with my chargers on. The risk is extremely low, but the severity of a lithium battery fire can be extreme, and you won't likely put it out with a household fire extinguisher.

 

[kahn]

I guess my answer mirrors the other two. I just use the bike and charge after each ride of more than 15 miles (which is usually my shortest ride), that way I'm prepared if the next ride will be 40 or 50 miles. I can't sweat the "small" stuff and attempt to eke out the longest battery life. Besides, unless you really do monitoring, the charger does not show the charge % and you can't preset it to some value. Hopefully, if I do kill the battery prematurely, Specialized will still offer replacements.

 

[m@Robertson]

Doesn't matter who makes the battery. The cells inside all pretty much share the same degradation rates. Overcharging is pretty much never an issue unless a cheap charger is involved, in which case said charger's reliability is suspect, to put the matter charitably.

The point about enjoying your bike vs. conserving the pack is a valid one. But don't make the mistake of minimizing the effect on lifespan. Its not 'slight'. Will 400 cycles be enough for you to decide you got the value you expected out of your pack? Everyone has their own answer. Decide how much you need to get where you are going and try to limit your charging if you can. Try to never let a pack sit - even overnight - at 100%. Thats when the degradation is the worst. Ideally you charge to 80% and, if you plan a longer ride that day, plug in first thing in the morning. I do that right when I get up and the time spent in the shower/shaving/brushing my teeth and pooping is time I'm also pushing the charge up to 100%. I start riding as soon as I unplug. Do it that way and you're degrading the pack very, very little.

The top article is the most approachable by the layman. The one on the bottom the more technical, but its citing Jeff Dahn, who if you poke around was then and remains the leading scientific expert on this subject.

Are you killing your lithium batteries?

Lithium-ion batteries are expensive, and large battery packs such as those in everything from electric cars to electric motorcycles and...

electrek.co

How to make a lithium battery last, or…kill it, if you like.

We have written in the past about tips that will help your expensive lithium battery pack last as long as possible. This article will cover some additional information about what happens inside the…

www.electricbike.com

From the first article linked above:

What causes these parasitic reactions to kill lithium-ion batteries?​

There are basically two main factors that speed up the inevitable death of your battery:

• High temperatures
• Increased time spent at high voltages (i.e. high charge level)

Both of these contribute to faster death of lithium-ion batteries. According to Jeff Dahn, high temperatures aggravate the parasitic reactions that occur in a lithium-ion battery’s electrolyte, while high charge levels result in extra performance for a few cycles, followed by a crash in performance and much faster deterioration of the cell.

 

[PedalUma]

I use a setup whereby I routinely charge to 90%. If you need the final 10% then top it up just before a ride, so it is not sitting at 100% for more than several minutes. I do not think that Specialized lets you fully charge to 100% but cuts of at closer to 95%, so do not worry about it too much. It is a tool meant to be used. Enjoy. I explained to someone yesterday about the ions this way. They flow from one side to the other in a stream. Like people on a game court. If all of them are against one wall for a length of time, some of them get stuck there. The charger moves them to one side, discharge to the other. The ions are also like plumbing or air pressure. If you pump a ball to 100% capacity, you would wreck it if you stored it that way for any period of time.

 

[PedalUma]

Doesn't matter who makes the battery. The cells inside all pretty much share the same degradation rates. Overcharging is pretty much never an issue unless a cheap charger is involved, in which case said charger's reliability is suspect, to put the matter charitably.

The point about enjoying your bike vs. conserving the pack is a valid one. But don't make the mistake of minimizing the effect on lifespan. Its not 'slight'. Will 400 cycles be enough for you to decide you got the value you expected out of your pack? Everyone has their own answer. Decide how much you need to get where you are going and try to limit your charging if you can. Try to never let a pack sit - even overnight - at 100%. Thats when the degradation is the worst.

The top article is the most approachable by the layman. The one on the bottom the more technical, but its citing Jeff Dahn, who if you poke around was then and remains the leading scientific expert on this subject.

Are you killing your lithium batteries?

Lithium-ion batteries are expensive, and large battery packs such as those in everything from electric cars to electric motorcycles and...

electrek.co

How to make a lithium battery last, or…kill it, if you like.

We have written in the past about tips that will help your expensive lithium battery pack last as long as possible. This article will cover some additional information about what happens inside the…

www.electricbike.com

Good stuff. We both posted at the same time. I did not see yours.

 

[m@Robertson]

yeah so I see

 

[tomjasz]

The answer is very simple:

• You might be paranoiac about the battery health and keep the charge between 20 and 80% and ride nowhere, or
• Use the battery with no fear, charging it to 100% and discharging down to 5% and enjoy long rides.

Yes, using the battery 100-5% shortens its life. Who cares? Not I.

P.S. Of course, the quality batteries as the ones from Specialized are protected against overcharging. It is even possible to charge the already charged battery to balance the cells. There is one question: Is the battery longevity or riding more important to you?

 

[PedalUma]

This is a wild one. Hint: Starts with the letter A.

 

[rich c]

I have two 2016 model year Haibikes with Bosch drive trains. I've charged to 100% every time and still going strong. 7,050 miles on one, 3,860 on the eMtb. You decide.

 

[Stefan Mikes]

For some people, it is riding that matters, not crying over the spilt battery health.

Let me paraphrase the evergreen statements of the British author of year 1900 (Jerome K. Jerome, "Three Men on the Bummel")

"There are two ways you can get exercise out of an e-bike: you can 'DIY' it, or you can ride it. On the whole, I am not sure that a man who takes his pleasure DYI-ing does not have the best of the bargain. He is independent of the weather and the wind; the state of the roads troubles him not. Give him a multimeter, a Grin Satiator, and something to sit down upon, and he is happy for the day. He has to put up with certain disadvantages, of course; there is no joy without alloy. He himself always looks like a tinker, and his machine always suggests the idea that, having stolen it, he has tried to disguise it; but as he rarely gets beyond the first milestone with it, this, perhaps, does not much matter. The mistake some people make is in thinking they can get both forms of sport out of the same machine. This is impossible; no machine will stand the double strain. You must make up your mind whether you are going to be a 'DIYer' or a rider."

 

[tomjasz]

I have two 2016 model year Haibikes with Bosch drive trains. I've charged to 100% every time and still going strong. 7,050 miles on one, 3,860 on the eMtb. You decide.

Superiority complex. The exception not the rule . Old buddy here went 14,000 miles. For $1000 sex should be included. You Bosch fellas crack me up.

 

[6zfshdb]

It's often a question of which will kill a battery first, age or use? They don't last forever on the shelf.

I bought 5 batteries when I purchased my 2 bikes in 2018. One has never been used. the others are stored at between 40 - 60%, charged to 100% just before a ride and have had roughly 200 charge cycles. Recent bench tests show that in 4 years, the unused battery has lost 3% of it's capacity while the ones in use have lost between 5 and 7% of capacity.

While all of us want our batteries to last, many of us need range and can't afford to charge to 80%. You can't have it both ways. Every rider has their own battery care regimen that suits their particular style. I believe in using the battery to it's full capacity and enjoying the sport. At the present rate, my batteries will likely outlast the useful life of the bike. YMMV.

It should also be noted that batteries usually don't die completely all at once. They lose capacity with time & use but can still be used as range extenders even at half capacity or below.

 

[rich c]

Superiority complex. The exception not the rule . Old buddy here went 14,000 miles. For $1000 sex should be included. You Bosch fellas crack me up.
View attachment 118510

Nope, just sharing actual experience. No folk tales repeated from something read on the internet, just simple facts.

 

[m@Robertson]

I have two 2016 model year Haibikes with Bosch drive trains. I've charged to 100% every time and still going strong. 7,050 miles on one, 3,860 on the eMtb. You decide.

The battery chemistry is what it is and its degradation will still occur. Holding your breath and closing your eyes will not affect this.

As was stated... its up to you to decide if that lesser lifespan gives you sufficient value for the dollar. If so, thats great. But don't delude yourself into thinking the degradation isn't happening. It is but you are ok with that because the battery is still long-lived enough that you don't sweat it.

Thats the thing here. Not to decide oh golly I have to conserve my pack and ride less. Make an informed decision to do as you please.

 

[m@Robertson]

Nope, just sharing actual experience. No folk tales repeated from something read on the internet, just simple facts.

Actually what you said is the opposite. Purely anecdotal True Battery Tales. The scientific evidence - this is not Bigfoot we are talking about - is not open for debate... and abundant. You wouldn't question whether you can strip the threads on a bolt by overtorqueing a nut - Thats perhaps a simpler concept that everyone can easily grasp ... and understand there is no debate there either. This is similarly a defined physical product with known limits, where those limits can be affected by use. End of story.

The debate is whether or not you are happy with what you are getting for the use you are putting it to. What @Stefan Mikes is saying further on in the thread is accurate. He doesn't care because he'd rather ride and enjoy it without giving a damn. there's nothing wrong with that.

The problem here is with the initial responses that gave flat out wrong information to someone asking for help to understand the issue. Feeding them BS is not an appropriate response and deserves to be corrected. Its the decent thing to do. Let them decide, knowing facts.

 

[mschwett]

Actually what you said is the opposite. Purely anecdotal True Battery Tales. The scientific evidence - this is not Bigfoot we are talking about - is not open for debate... and abundant. You wouldn't question whether you can strip the threads on a bolt by overtorqueing a nut - Thats perhaps a simpler concept that everyone can easily grasp ... and understand there is no debate there either. This is similarly a defined physical product with known limits, where those limits can be affected by use. End of story.

The debate is whether or not you are happy with what you are getting for the use you are putting it to. What @Stefan Mikes is saying further on in the thread is accurate. He doesn't care because he'd rather ride and enjoy it without giving a damn. there's nothing wrong with that.

The problem here is with the initial responses that gave flat out wrong information to someone asking for help to understand the issue. Feeding them BS is not an appropriate response and deserves to be corrected. Its the decent thing to do. Let them decide, knowing facts.

in some ways, what both @Stefan Mikes and m@robertson are saying is true and relevant. if you don't use your e-bike daily, charging it to 100% and leaving it at 100% for a week is not good for the battery.

but if you ride it every day, and then plug it in and ride it 12 hours later, the amount of time at full charge is fairly small, as stated in the first source reference above:

If you are planning a long trip and will be heading out shortly after you finish charging, a 100% charge will have very little impact on your battery’s lifespan. However, if you will be leaving your battery unused for many days or weeks, a charge level of between 30-60% is much healthier for the batteries over the long-term.

i haven't seen any actual research correlating the decrease in lifespan to the interval between full charge and partial discharge from use, but one could assume results somewhere in between the 100% (500 cycles) and 80% (1500 cycles.)

 

[m@Robertson]

Tru dat. But from the standpoint of maximum anal retentiveness, finish charging just before you hit the road so the opportunity for negative waves is at a minimum. Leaving the pack charged for the next ride next Tuesday is where the Angels start weeping and God reaches for that kitten...

Usually in these discussions I outline the specifics, and then say "don't let that stop you from riding the s*it out of the bike. They are there to be enjoyed."

 

[Gionnirocket]

I agree with most of what has been said.
First and foremost... Using the battery as needed for full enjoyment of riding takes priority.
That said I can charge my battery to 85% and get my 20+ mile daily ride done and return home with 65%
This works well for me as I don't necessarily need to charge the next day to get another ride in and if I do charge back to 85%, it's done rather quickly.
Also if I get busy or rained out for a few days, especially in the winter... 65% is a pretty good storage state.
So for me on most days charging to 100% has no advantage. On longer rides charging to 100% early that morning from 85% is done quickly and easily without stressing me or the battery much.