Is this "charging formula" correct ?

[Nakiri]

Well, I'm new in this e-Mtb world. I was reading some posts about battery care/recharging and ended up in this website:

BU-808: How to Prolong Lithium-based Batteries

BU meta description needed...

batteryuniversity.com

And I'll quote some infos from there:

"Most Li-ions charge to 4.20V/cell, and every reduction in peak charge voltage of 0.10V/cell is said to double the cycle life."
"For example, a lithium-ion cell charged to
4.20V (100%) cell typically delivers 300–500 cycles...
3.90V (60–65%) cell should provide 2,400–4,000 cycle "


And then...
"On the negative side, a lower peak charge voltage reduces the capacity the battery stores. As a simple guideline, every 70mV reduction in charge voltage lowers the overall capacity by 10 percent. "


BUT:
"Applying the peak charge voltage on a subsequent charge will restore the full capacity."


What I've concluded from those infos:

If I charge the battery to 65% on one ride and 100% in the next one... I'll not have the reduced capacity issue... and the cycle life life will be up to (500 + 4000)/2 = 2.250 cycles.

Is this assumption correct ? Or am I being too simplistic ?
Of course, assuming that I can ride the trails with only 65% of the battery.


Thanks !!!!

 

[CJaMTB]

Try starting with the manufacturer's recommendations...

 

[Alexbn921]

First things first. Buy a wifi plug timer so you can control the charging.

You want to store the battery at 50-60% charged. This is 3.85v per cell.

Before you ride charge it to 100%. This is important to do at least once every couple rides as balancing only starts at around 95%.

NEVER STORE YOUR BATTERY AT 100%

Try not to discharge your battery below 10%. Running it all the way down until limp mode damages it.

As long as you "take care" of your battery it will last for a decade, so don't worry about the exact number of cycle you will get out of it.

Length of time at full and zero charge are what destroy batteries.

 

[CJaMTB]

First things first. Buy a wifi plug timer so you can control the charging.

Great shout, forgot that!

 

[Nakiri]

First things first. Buy a wifi plug timer so you can control the charging.

Hummmm....I don't know how do I suppose to use it.
Plug my bike.... and how do I know when to turn it off ? Will it be just an educated guess on how much time it will have to be "on" to reach 65% ?

Could you give me some tips on how to usethis plug timer ?


Thanks !

 

[dobbyhasfriends]

overthinking it IMO charge it, ride it, charge it, ride it.
repeat.

 

[Alexbn921]

My battery is 20 amp hours and my charger is 4 amps. 20/4 = 5 hours to charge or 20% per hour.
If I end a ride with 20%, I plug it in and set the timer for 2 hours. 20% + (20% x 2)= 60%.
I tend to store closer to 60% so it only takes 2 hours to fill up. This doesn't need to be exact. Just get it in the middle and you will be fine.

This is the timer I use:
Kasa Smart Plug Mini 15A

You can turn it on from anywhere so its ready when you get home or set it to charge in the morning before you get up.

 

[Nakiri]

overthinking it IMO charge it, ride it, charge it, ride it.
repeat.

You're kinda right.
But I live in Brazil and the reality here is a little bit different.Think like if a replacement battery would cost about US$11.000 for you.

So, for my reality, I want the battery lasts for my entire life... lol
I'm not that dude that can afford to buy a new bike every year. I use to keep it for several years before sell/buy another.

That's why I want to take the best care of my battery.


Cheers !

 

[Nakiri]

My battery is 20 amp hours and my charger is 4 amps. 20/4 = 5 hours to charge or 20% per hour.
If I end a ride with 20%, I plug it in and set the timer for 2 hours. 20% + (20% x 2)= 60%.
I tend to store closer to 60% so it only takes 2 hours to fill up. This doesn't need to be exact. Just get it in the middle and you will be fine.

This is the timer I use:
Kasa Smart Plug Mini 15A

You can turn it on from anywhere so its ready when you get home or set it to charge in the morning before you get up.

I didn't think of this MATH. Now I know how to use it... hahaha
I'll just find out the specs of the Levo 2019 battery and charger !


Thanks !

 

[Alexbn921]

levo 500 is 15 amp hours and 700 is 20. Charger should say the output amps on it.

 

[DaveW2]

My battery is 20 amp hours and my charger is 4 amps. 20/4 = 5 hours to charge or 20% per hour.
If I end a ride with 20%, I plug it in and set the timer for 2 hours. 20% + (20% x 2)= 60%.
I tend to store closer to 60% so it only takes 2 hours to fill up. This doesn't need to be exact. Just get it in the middle and you will be fine.

This is the timer I use:
Kasa Smart Plug Mini 15A

You can turn it on from anywhere so its ready when you get home or set it to charge in the morning before you get up.

Great idea. But is there any chance that powering up the charger while it is connected to the battery is bad for the battery? This would happen if you turned on the smart plug remotely to get it charged for a ride. Orbea instructions for the EP8 RS say to plug in the charger before connecting it to the battery.

 

[urastus]

I generally charge to 80%. Once a month I leave it charging till it shuts down (full charge on a shimano system). The 80% charge has saved me a few times where I've intended to ride, but haven't for weeks and even months.

Of course, if I needed more, I'd charge to 100%. I use a timer, so I'd have it finish charging not too long before I was going to ride it.

 

[RustyIron]

Is this assumption correct ? Or am I being too simplistic ?
Of course, assuming that I can ride the trails with only 65% of the battery.

Most of my rides use up about 80% of the battery, so rolling out with a partial charge isn't feasible. When I get home after a ride and the battery is at <10%, I'll put it on the charger at least for a couple hours. If there is a chance I'll ride the next day, I'll plug it in until it's done. If I definitely won't be riding the next day, that I'll postpone charging.

I look at the battery as a sacrificial part of the bike, like tires and pads. It's not going to last forever. If I have to replace it before I sell the bike, then that's what I'll do. But if I miss a ride because my battery was low, then that would be a bummer.

 

[Kingerz]

"Try not to discharge your battery below 10%. Running it all the way down until limp mode damages it."

Not for sure...Panasonic/giant says to fully discharge every 3 months or 15 cycles and they know their stuff.

On these press the button on the smart charger to get it to charge to 60% and shut off.

I recommend people just rtfm for their bike.

Exception: Specialized always say their bikes have 100% battery health even after 4 years of abuse lol.

 

[robbydobs]

Just do what the manufacturer says.

Most branded batteries by large manufacturers (Shimano, Giant etc) will have a battery management system that manages all this.
The battery won't let you run any of the cells in the battery pack down to 0%. If it says 0% on the display, they'll be a few % left in each cell to avoid damage. Similarly with fully charging the battery.

Try not to mix up cells vs a battery pack with is managed by a processor.

 

[Nakiri]

I kinda understand opinion that says "read the manual".
BUT... Imagine if SPZ (for example) starts to write in their manual: "Don't go up to 100% all times, if you let the bike for a period without use, leave it at 60%. But if it's for a short, no problem. But if you let it at 60%, next time go fot 100%. Buy a wifi timer, check the amps"... lol

In my opinion, they gave us the lesser of two evils. Not the best care cenario, because it's complicated and most of riders don't give a *** about it.


Cheers !

 

[Mike D.]

Storing longer than 2 months: 70%
Storing below 10c temp. Don't do it.
Start charge up after 30 minutes rest post-ride.

Anything else is WAAAAY too granular.

Happy trails.

 

[Repsol]

I get that people want to protect their battery and get the most out of it but part of me thinks this is a load of bollocks. Do you honestly think the manufacturer follow this 65% storage rate?....... no they don't.
My brand new specilized bike which was returned and replaced, had only 30% charge on it. This proves the manufacturer don't charge them properly at all. All the dealer does is his PDI check which should include charging it fully to 100% anyway, so your never none the wiser unless they forget to do it, as in my case.

I wonder how many others have had their bikes delivered with less than 100% charge in it, and how many are sat on the shop floor waiting to be sold at exactly 65%.

 

[Alexbn921]

Having spent $1000's on batteries and chargers over the years for RC car and planes, I can 100% say that how you treat your batteries has a direct and noticeable effect on their life. I get 2-3X the life out of batteries now then when I didn't care.

If you don't care and your advise is don't care, take it at face value.

If you do care, then protecting your investment will pay off. It's easy and doesn't take me any time as its already part of how I maintain the 40+ other batteries I have.

 

[flash]

I get that people want to protect their battery and get the most out of it but part of me thinks this is a load of bollocks. Do you honestly think the manufacturer follow this 65% storage rate?....... no they don't.
My brand new specilized bike which was returned and replaced, had only 30% charge on it. This proves the manufacturer don't charge them properly at all. All the dealer does is his PDI check which should include charging it fully to 100% anyway, so your never none the wiser unless they forget to do it, as in my case.

I wonder how many others have had their bikes delivered with less than 100% charge in it, and how many are sat on the shop floor waiting to be sold at exactly 65%.

There's a difference between a new battery that has yet to be initialised and general storage. 30% is quite reasonable for an uninitialised battery. For a brand new battery generally a couple of full or close to full cycles is recommended so the BMS can balance the cells properly after the first couple of rides. You can't return the bettery to that uninitialised state so 60-70% is recommended because lithium batteries don't like general storage at a high or low SoC.

Gordon

 

[flash]

Great idea. But is there any chance that powering up the charger while it is connected to the battery is bad for the battery? This would happen if you turned on the smart plug remotely to get it charged for a ride. Orbea instructions for the EP8 RS say to plug in the charger before connecting it to the battery.

No. It won't make a difference. The charger and BMS don't care. The only possibility would be a tiny loss of charge if the battery is plugged into the charger although I've seen no evidence of this on my Shimano or Fazua chargers. I think they're smarter than that.

Gordon

 

[urastus]

new specilized bike which was returned and replaced, had only 30% charge on it

From when? Batteries do lose charge over time. 30% is fine; most battery nerds suggest between 30 and 60% for storage. I would be concerned if it was 100% or flat.

 

[Frank_Denmark]

This could be the solution for You - Charger controlled by app...

Smart, battery-friendly charging
The LiON Smart Charger gives you the choice of fast (partial) charging on the go or gentle, slow charging to support maximum battery longevity. You can select and monitor the charging scenes individually or pre-programmed in the handy app.

Users could set the charging current (1/2/3/4A) and the maximum charging percentage of battery. Users could also set a reminder alarm after time estimation from the LiON.

Shop

 

[Frank_Denmark]

I get that people want to protect their battery and get the most out of it but part of me thinks this is a load of bollocks. Do you honestly think the manufacturer follow this 65% storage rate?....... no they don't.
My brand new specilized bike which was returned and replaced, had only 30% charge on it. This proves the manufacturer don't charge them properly at all. All the dealer does is his PDI check which should include charging it fully to 100% anyway, so your never none the wiser unless they forget to do it, as in my case.

I wonder how many others have had their bikes delivered with less than 100% charge in it, and how many are sat on the shop floor waiting to be sold at exactly 65%.

When transporting the bike/battery Spezialized recommend approx 30% charged
From Gen3 manual

 

[Frank_Denmark]

More info from the Levo Gen3 manual

 

[urastus]

I kinda understand opinion that says "read the manual

with new cars and motorcycles, the "manual" generally says there is no need to warm up the motor. Unless, of course, you have a high end sports bike / car. Enthusiasts generally warm up their engines. The consensus is that the average car serves a different purpose for the intended owner. Two of those sort after qualities are good fuel economy and ease of ownership. Warming up a car for 5 minutes would use up a liter of fuel? That effects the fuel economy, and the ease of use. I wince when I see those people pull out into traffic blowing lots of smoke as they try to floor a cold car. A sports bike or car; they're usually owned by people with different priorities - performance. It's usually taken for granted that high performance is not low maintenance (not everyone knows this). The owners of these bikes / cars are usually enthusiasts and have some knowledge.

The manual...what is the goal of the folk who wrote that manual? Their goal may not be yours.

 

[Repsol]

More info from the Levo Gen3 manual

View attachment 82197

View attachment 82198

Anyone got the number for specsavers lol.
I read my manual from end to end and never saw that, I'll have another look as I'm wondering if either I've got another edition or it wasn't included in the black zipper wallet.

 

[urastus]

This could be the solution for You - Charger controlled by app...

Smart, battery-friendly charging
The LiON Smart Charger gives you the choice of fast (partial) charging on the go or gentle, slow charging to support maximum battery longevity. You can select and monitor the charging scenes individually or pre-programmed in the handy app.

Users could set the charging current (1/2/3/4A) and the maximum charging percentage of battery. Users could also set a reminder alarm after time estimation from the LiON.

What an awesome setup. Strange though, nothing for shimano!

 

[Frank_Denmark]

Anyone got the number for specsavers lol.
I read my manual from end to end and never saw that, I'll have another look as I'm wondering if either I've got another edition or it wasn't included in the black zipper wallet.

Page 27

 

[1oldfart]

I am all with post # 6. i get home from riding = i charge.
I think this site is about riding???
I ride daily, no time to solve stuff.