Battery Life extension.

[Shifty]

I noticed that keeping my battery topped up after short rides has used up 5 battery cycles. Knowing that after a few hundred cycles the battery and charger become less effective this isn’t a good thing to do.
So now I am running the battery down on my trips during the week and reducing my charge top ups to a minimum. Charging twice a week using two cycles instead of every night I’m out using 5 a week!
What’s your thoughts??

 

[DrStupid]

I do the same, and never fast charge. Charge only when its gets to two lights left.
I'm at 18 cycles and battery showing 95% efficiency.

 

[Husky430]

Wow, not sure how to check my battery health (Shimano engine and battery in a Merida) but I would have thought that loosing 5% battery efficiency in only 18 charges is not good. I thought you are suppose to get 500-700 charging cycles out of a battery?

 

[DrStupid]

Yeah, I am on the same page, but I'm not terribly worried about it yet. If it continues to get worse, I'll start complaining to the dealer and see where that goes.

I haven't investigated how this score is determined?

 

[HikerDave]

I noticed that keeping my battery topped up after short rides has used up 5 battery cycles. Knowing that after a few hundred cycles the battery and charger become less effective this isn’t a good thing to do.
So now I am running the battery down on my trips during the week and reducing my charge top ups to a minimum. Charging twice a week using two cycles instead of every night I’m out using 5 a week!
What’s your thoughts??

Don’t run the battery all the way down and don’t keep the battery topped up; batteries are best stored between 20 and 80 percent charge but you should charge fully to equalize the cells. I charge about twice a week too; 2600 miles and still less than 100 charge cycles.

 

[Shifty]

Wow, not sure how to check my battery health (Shimano engine and battery in a Merida) but I would have thought that loosing 5% battery efficiency in only 18 charges is not good. I thought you are suppose to get 500-700 charging cycles out of a battery?

It’s not battery efficiency that’s being lost. Giant count charging cycles and when it reaches so many (think it’s 500) cycles Giant reduce the charging efficiency on purpose to keep the battery more efficient for longer.

So that’s why it’s best only to charge when the battery is low and not keep it topped up. As each little top up uses 1 charging cycle.

 

[Wernher]

It’s not battery efficiency that’s being lost. Giant count charging cycles and when it reaches so many (think it’s 500) cycles Giant reduce the charging efficiency on purpose to keep the battery more efficient for longer.

So that’s why it’s best only to charge when the battery is low and not keep it topped up. As each little top up uses 1 charging cycle.

@Shifty it is not true that every charge counts as a cycle. I've charge my bike regularly with as much as 70% battery left and the count only goes up for full charge cycles. My battery condition is still at 98% with more charging cycles done than on yours. What I also picked up is that my battery condition goes down sometimes by 1% after I depleted it to approximately 11% remaining battery, but went back to 98% after one or two subsequent charges where I didn't punish it so hard (charged with more battery remaining).

The Giant battery is made by Panasonic and is extremely well made. It is one of the batteries that will last longer than any other battery out there and certainly on par with anything else out there. You can stop worrying about your battery and just use it. It will last a very long time and you'll probably have a new bike long before that happens. They are also bringing out new batteries with longer range that is lighter and you might want to buy one of those when it becomes available. Trust me, you will not kill your battery, but you might shorten is life of you keep running it to empty.

 

[Shifty]

@Shifty it is not true that every charge counts as a cycle. I've charge my bike regularly with as much as 70% battery left and the count only goes up for full charge cycles. My battery condition is still at 98% with more charging cycles done than on yours. What I also picked up is that my battery condition goes down sometimes by 1% after I depleted it to approximately 11% remaining battery, but went back to 98% after one or two subsequent charges where I didn't punish it so hard (charged with more battery remaining).

The Giant battery is made by Panasonic and is extremely well made. It is one of the batteries that will last longer than any other battery out there and certainly on par with anything else out there. You can stop worrying about your battery and just use it. It will last a very long time and you'll probably have a new bike long before that happens. They are also bringing out new batteries with longer range that is lighter and you might want to buy one of those when it becomes available. Trust me, you will not kill your battery, but you might shorten is life of you keep running it to empty.

Thank you , on my Giant it is true! On the Giant app it shows 5 cycles and I have only ever once got down to two bars and all the other times is from putting the charger in with 4 bars still left most nights. I have only had the bike a couple of weeks.
So..... I will monitor it! And report back !!

 

[Wernher]

I have a Giant Trance-E +2 and the cycles don't count up for every part charge. They also state that in the manual and I've checked it. If your cycles are higher than you think it should be, your battery might have been charged before you purchased it. I charge full before a long ride and otherwise if I do short rides around my home usually recharge when I get around 50%. Condition remains around 98%. Anyway believe be me that battery will last a very long time.

 

[MattyB]

@Shifty it is not true that every charge counts as a cycle. I've charge my bike regularly with as much as 70% battery left and the count only goes up for full charge cycles. My battery condition is still at 98% with more charging cycles done than on yours. What I also picked up is that my battery condition goes down sometimes by 1% after I depleted it to approximately 11% remaining battery, but went back to 98% after one or two subsequent charges where I didn't punish it so hard (charged with more battery remaining).

Sorry, that just isn't correct - correlation does not imply causation. Your battery (as with all ebike batteries from the major manufacturers) has a BMS in it which prevents discharge down to levels where permanent damage could be caused to the cells (generally considered to be anything below a resting voltage of 3.0-3.2V/cell). If your battery health went down after that ride any number of factors could have influenced it (ambient temp, rate of discharge, number of cycles, calculated internal reistance etc etc), especially given we have precisely zero knowledge of how Giant of any of the other manufacturers calculate "battery health". Put simply there is no danger in discharging your packs down to "fully flat" on any big brand ebike, as "fully flat" will still be a safe resting voltage.

...The Giant battery is made by Panasonic and is extremely well made. It is one of the batteries that will last longer than any other battery out there and certainly on par with anything else out there. You can stop worrying about your battery and just use it. It will last a very long time and you'll probably have a new bike long before that happens. They are also bringing out new batteries with longer range that is lighter and you might want to buy one of those when it becomes available. Trust me, you will not kill your battery, but you might shorten is life of you keep running it to empty.

The Giant batteries are exactly the same chemistry as every other brand, but are constructed to a slightly different safety standard (which they did because they thought there may be a chance they could be legally transported by air at some point in the future). This means they may run very slightly cooler at a given discharge rate, which in theory may give them a slightly longer cycle life.

In practice this is a tiny influence compared to how battery is used and stored by the owner - in particular the ambient temp and state of charge it is stored at will be far more influential in cycle life. Charge it to full straight after every ride in a warm climate and you will kill it way faster than if you store at 20-70% charge, charge to full just before you ride and keep in a cool place.

Lots of threads on this topic are available in the forum, have a gander...

Battery care/management - EMTB Forums
Loss in battery life - EMTB Forums
Battery Management - EMTB Forums

...and here's some external resources explaining the factors that influence cycle life, capacity degradation and power density over time...

How to Prolong Lithium-based Batteries - Battery University
Three Ways That Lithium Dendrites Grow

 

[MattyB]

PS - There is not much point in a smart charger that changes the charging profile at 500 cycles unless that charger has the ability to accurately count partial cycles. It's sound theory they are basing it on, but sounds like a pretty half cocked implementation.

 

[Shifty]

I have a Giant Trance-E +2 and the cycles don't count up for every part charge. They also state that in the manual and I've checked it. If your cycles are higher than you think it should be, your battery might have been charged before you purchased it. I charge full before a long ride and otherwise if I do short rides around my home usually recharge when I get around 50%. Condition remains around 98%. Anyway believe be me that battery will last a very long time.

That’s vey helpful thank you
, I bought my bike on-Line and the battery was already at 60% charge! So it may be an old battery but not a lot I can do about it.
Anyway I see Giant have just released a water bottle holder top up battery for 2020 plugs into the charging port so hopefully they will fit my 2019.

 

[Pukmeister]

AFAIK the Giant batteries come with a 60% deep storage charge when new and the battery is unlocked from its deep storage state the first time it talks to the smart charger.

As for the 2020 bikes having a water bottle mounted range extender battery, the pre-release photos I saw showed an extra two pins in the charging port compared to my 2019 bike so the Jury is out on that one. I have asked about aftermarket range extenders for 2019 Giants already and as yet they are not available.

 

[HikerDave]

That’s vey helpful thank you
, I bought my bike on-Line and the battery was already at 60% charge! So it may be an old battery but not a lot I can do about it.
Anyway I see Giant have just released a water bottle holder top up battery for 2020 plugs into the charging port so hopefully they will fit my 2019.

Perfect. You’re much better off with a battery that was stored at the optimal 60 percent instead of a battery that was kept topped up at a bike shop.

The range extender is nice; I’ve only been on one ride where I could have used one, though - and that’s with only a 400 wH battery. My usual weekend ride of 7 fast road miles and 13 leisurely trail miles (with occasional bursts of spirited riding) uses about half my battery.

 

[DrStupid]

I worded my previous message wrong. Its battery health... not efficiency.

See below.

Either way I'm not doing anything weird with it?. Its only dropped below 2 lights on the charge indicater once, and only stayed there for about 20 minutes. I ride every day, so it's never fully charged more than 12 hours, and I only charge once it's at 2 lights left, unless I'm planning a big workout the next day.

 

[Bilko]

I would take what ride control says with a pinch of salt. My year old battery is in better health than my 2 week old one.

 

[DrStupid]

Are you all charging on the bike or off? I always charge on the bike, but maybe the balancing or ... ??? Doesnt work as well on the bike, and that's why my battery seems not so healthy?

 

[Bilko]

Good point, the old battery has always been charged off the bike, the new one has been charged on the bike except the first charge. Also the old battery charger is 4 amps the new 6 amps.

 

[DrStupid]

Good point, the old battery has always been charged off the bike, the new one has been charged on the bike except the first charge. Also the old battery charger is 4 amps the new 6 amps.

I read that the new chargers only use the 6 amp charge when the battery is off the bike.

I'm going to start charging off the bike and see what happens... if anything.

 

[Wernher]

Are you all charging on the bike or off? I always charge on the bike, but maybe the balancing or ... ??? Doesnt work as well on the bike, and that's why my battery seems not so healthy?

I charge on and off. The balancing happens in the battery and not in the charger so there's no difference. Like others have said, Ride Control isn't always right. My battery condition sometimes shows an improvement.

 

[Wernher]

Also it's better to wait for your battery to cool down a bit before you charge, but not essential.

 

[DrStupid]

Point taken. My battery is never even warm after a ride. Do you all experience a battery much warmer than ambient after a ride?

 

[MattyB]

The battery is only likely to get hot in warmer climbs (say 25C+), and even then only during period of high load where it is operating at peak wattages for a decent period. Most of the discharge is at 0.25-0.5C (i.e. it will take between 2 and 4 hrs to fully discharge the pack), and at that kind of current heat build up due to discharge will be pretty low; leaving it for 5-10 mins after charging is all you will need to do, if that.

 

[Wernher]

The battery is only likely to get hot in warmer climbs (say 25C+), and even then only during period of high load where it is operating at peak wattages for a decent period. Most of the discharge is at 0.25-0.5C (i.e. it will take between 2 and 4 hrs to fully discharge the pack), and at that kind of current heat build up due to discharge will be pretty low; leaving it for 5-10 mins after charging is all you will need to do, if that.

Agreed. I am in the habit to let it "rest" a bit from my days off flying RC Choppers ? in that application the batteries became quite hot. The new batteries as found in the ebikes are in a new league. The Giant batteries as manufacturers by Panasonic is incredibly safe with large gaps between the cells with a cooling paste inbetween. That's why the batteries are so much heavier than the Shimano, Bosch and Specialized batteries.

 

[DrStupid]

Good point, the old battery has always been charged off the bike, the new one has been charged on the bike except the first charge. Also the old battery charger is 4 amps the new 6 amps.

Two charges off the bike, and the health has gone up one % to 96. Last two cycles were deep, taking the battery down to one indicator light and then charged off the bike. I'm gonna keep doing this (charge off the bike) and watch. Its mostly just a curiosity to me now. Where its charged either effects Giants health score, or it doesn't. Inquiring minds want to know.

Whether or not Giants health score is meaningful, or accurate, is another question all together.

 

[Alcove]

I got my bike in Dec and initially had it setup charging on the bike in the garage. Couple weeks in noticed the battery health dropped to 96% so started charging off the bike and inside the house. Since then has remained stable at 96% but I notched that up more to the charging temperature but maybe off bike may play a factor too....

 

[KuRi]

Hi! Mine is at 96% after 16 cycles and 3 months. I think it is too low and the LBS will check the bike next week

Cheers!

 

[MattyB]

Whether or not Giants health score is meaningful, or accurate, is another question all together.

Exactly. All these scores are meaningless unless you understand how they are calculated, and none of the manufacturers tell us that. The only thing they are useful for is a very crude comparison between to packs of the same make and model, but even that will not factor in differences which can mean significantly different ranges being returned from packs of identical "health" (ambient temp, climbing metres vs flat, time in different power modes etc).

 

[Shifty]

I just charge and ride, not bothered about what the App says on %. I think I would know if the battery was knackered without having to look at the % on the App. Just don't think 98% 96% means anything to me practically.

 

[DrStupid]

KUri, your battery health is about where Bilko's and mine is. I predict your dealer will say it's fine, but who knows.My guess is that this is a typical reading. Let us know, if yours gets swapped out, then dam it... I want a new one too.

I dont know how Giant decided to rate battery health, but its not a simple thing to determine.

Battery State of Health Determination