Small discovery…

Oldcrank

Member
Jan 5, 2020
67
54
Albuquerque NM
I’ve a Stance 2021 and read that the charger can hold the charge to 60% for better battery life. Tried it and sure enough, it charged to 4 of 5 charge indicating lights. This is perfect for the length of rides I do AND helps battery life. :cool:
 

DaveMatthews

Well-known member
Aug 12, 2018
479
323
Vancouver, B.C. Canada
I’ve a Stance 2021 and read that the charger can hold the charge to 60% for better battery life. Tried it and sure enough, it charged to 4 of 5 charge indicating lights. This is perfect for the length of rides I do AND helps battery life. :cool:
I knew of the feature. It's for long term storage, but haven't used it regularly.
 

Kiwi Giant

Active member
Feb 11, 2020
119
134
New Zealand
Unfortunately the local terrain (hills) and the distances of my usual rides have me suffering from "range anxiety" on a daily basis so the 60% storage charge button would need to be relabelled "increase stress"!
 

Nicho

Captain Caption
Subscriber
Jan 4, 2020
1,048
1,923
Furness, South Cumbria.
I’ve a Stance 2021 and read that the charger can hold the charge to 60% for better battery life. Tried it and sure enough, it charged to 4 of 5 charge indicating lights. This is perfect for the length of rides I do AND helps battery life. :cool:

The 60% charge is for storage if you are not using the bike for a few weeks or months.
If you use this setting all the time you will find that your battery health will deteriorate quickly.
Every few charges you need to run the battery down to almost empty then recharge it up to 100%.
That will balance the cells and keep them working properly, helping to prevent the drop-off in battery health.
 

Kiwi Giant

Active member
Feb 11, 2020
119
134
New Zealand
Evolution Stu (from here) recently posted this very good explanation on the Giant E Bike Facebook page which explains battery charging and his charging regimen:

"Sadly there is a ton of miss-information out there and it’s made it very hard to know the truth about what’s best for the batteries.

The reality is that this is just Li-Ion technology and it follows the same rule as any battery of that typical chemistry make up.

Charging to around 60% is optimal, especially if using fast charging. Most modern Li-Ion batteries can take a high current charge to mid capacity with very little degradation of the cells. My 500wh battery goes from 0-60% in 1.5hrs using the 6amp fast and smart charger.

The problem is, charging more than that affects its life. That is because these batteries require a little Over-Volting to take them to full capacity and as such a step charging method is employed by the on board BMS. (Battery management system)

Spending long periods of time with charge levels far above 80% is accepted as the most harmful for this technology. To the point that it is technically better to charge the bike to 60% and flatten it 4x than to charge it to 100% and flatten it twice.

That’s the same reason that some manufacturers have a half charge or “Storage” button. These buttons typically halt charging at around 60% which is the batteries optimum capacity for mechanical longevity during storage long term. (Heat issues aside)

They certainly should also be fully charged from time to time in order for the BMS to balance the cells, it does this in rows of cells and it does this to maintain a balanced performance across the battery pack. It can only do that with a full charge occasionally.

People also worry about outside temperature.
These batteries work fine down to around zero degrees but may well not accept a charge below that. I believe storage between 10 and 20c is ideal. Heat is actually the enemy of this chemistry, not cold and a very warm battery being charged up will also shorten its life somewhat.

These things should take hundreds of full capacity charges without too much degradation. I recall Giant saying 1000+. But how much degradation is too much? I guess that depends on how much you need the batteries full range.

Bottom line for me is this.
When I come back from a ride I put the batteries on charge and charge them both to 60% using the storage charge button.
Only the night before a ride do I charge any of them up to 100%.

As far as I am concerned that is the optimum way to use these batteries and most big manufacturers of devices using this technology will agree with me.

For a good example of big manufacturers doing exactly this, look at the way modern phones now smart charge the battery so it only reaches 100% just before you wake up in the morning. This is for exactly the same reason."

I hope this helps.
 

urastus

⚡The Whippet⚡
May 4, 2020
1,548
995
Tasmania
How awesome! 60%, as others have said, is supposedly the ideal storage charge. I too rarely need a full charge, so I go to 80% most of the time. Once after the 4th or 5th charge I do a full charge for bms. The beauty of this setup for me is that sometimes I intend to ride but it just doesn't happen. Very wet weather or an injury has kept me off the bike for a few months at times, and I haven't had any warning of it. So my bike isn't at full charge for all that time - it is 80% or less. I use a programmable timer.
 

RustyIron

E*POWAH Elite World Champion
Subscriber
Jun 5, 2021
1,830
2,850
La Habra, California
Meh.
I'll continue to charge my battery fully, and find comfort in the knowledge that I won't have to worry about draining the battery. It's also nice to have the option of extending the ride because I have a fully charged battery.

If you have a 750 watt battery and ride it with a 60% charge, why not just just buy a bike with a 450 watt battery, charge it fully, and not have to carry the excessive weight of a battery you don't need?
 

urastus

⚡The Whippet⚡
May 4, 2020
1,548
995
Tasmania
If you have a 750 watt battery and ride it with a 60% charge, why not just just buy a bike with a 450 watt battery, charge it fully, and not have to carry the excessive weight of a battery you don't need?
You answered that question yourself. I generally do small daily rides at about 25% of a 504wh battery. I have the option of doing longer rides, and do use it especially when riding with others. The same could be said for the majority of cars, motorcycles - most of them do short trips, but have the capacity to do longer trips. How do you choose ideal battery size? For me, am I likely to need more than 504wh? Keep in mind that it isn't good at all to run your battery flat either. If we were machines and rode the same track at the same speed blah blah blah, but we're not. How much versatility do each of us need or want - that's the question. If I think I'm going to need more battery, I have the option to charge it to 100%. The reality is though that most of us won't get to choose the size of battery - we'll get whatever comes on the bike we choose.
 
Last edited:

1oldfart

Active member
Oct 6, 2019
684
321
Outdoors
Evolution Stu (from here) recently posted this very good explanation on the Giant E Bike Facebook page which explains battery charging and his charging regimen:

"Sadly there is a ton of miss-information out there and it’s made it very hard to know the truth about what’s best for the batteries.

The reality is that this is just Li-Ion technology and it follows the same rule as any battery of that typical chemistry make up.

Charging to around 60% is optimal, especially if using fast charging. Most modern Li-Ion batteries can take a high current charge to mid capacity with very little degradation of the cells. My 500wh battery goes from 0-60% in 1.5hrs using the 6amp fast and smart charger.

The problem is, charging more than that affects its life. That is because these batteries require a little Over-Volting to take them to full capacity and as such a step charging method is employed by the on board BMS. (Battery management system)

Spending long periods of time with charge levels far above 80% is accepted as the most harmful for this technology. To the point that it is technically better to charge the bike to 60% and flatten it 4x than to charge it to 100% and flatten it twice.

That’s the same reason that some manufacturers have a half charge or “Storage” button. These buttons typically halt charging at around 60% which is the batteries optimum capacity for mechanical longevity during storage long term. (Heat issues aside)

They certainly should also be fully charged from time to time in order for the BMS to balance the cells, it does this in rows of cells and it does this to maintain a balanced performance across the battery pack. It can only do that with a full charge occasionally.

People also worry about outside temperature.
These batteries work fine down to around zero degrees but may well not accept a charge below that. I believe storage between 10 and 20c is ideal. Heat is actually the enemy of this chemistry, not cold and a very warm battery being charged up will also shorten its life somewhat.

These things should take hundreds of full capacity charges without too much degradation. I recall Giant saying 1000+. But how much degradation is too much? I guess that depends on how much you need the batteries full range.

Bottom line for me is this.
When I come back from a ride I put the batteries on charge and charge them both to 60% using the storage charge button.
Only the night before a ride do I charge any of them up to 100%.

As far as I am concerned that is the optimum way to use these batteries and most big manufacturers of devices using this technology will agree with me.

For a good example of big manufacturers doing exactly this, look at the way modern phones now smart charge the battery so it only reaches 100% just before you wake up in the morning. This is for exactly the same reason."

I hope this helps.
Would you have a link for the Giant page?
 

Labrador29

Well-known member
Jun 24, 2019
210
173
Marlborough New Zealand
I’ve a Stance 2021 and read that the charger can hold the charge to 60% for better battery life. Tried it and sure enough, it charged to 4 of 5 charge indicating lights. This is perfect for the length of rides I do AND helps battery life. :cool:
It is recommended to charge to 60% if you aren't going to use your e-mtb for a while (storage purposes). My e--golf trundler is the same. Unless you aren't going to use your e-mtb for a while, full charge every time for peace of mind.
 

Evolution Stu

E*POWAH Master
Jun 30, 2019
457
448
Blackpool. U.K.
Meh.
I'll continue to charge my battery fully, and find comfort in the knowledge that I won't have to worry about draining the battery. It's also nice to have the option of extending the ride because I have a fully charged battery.

If you have a 750 watt battery and ride it with a 60% charge, why not just just buy a bike with a 450 watt battery, charge it fully, and not have to carry the excessive weight of a battery you don't need?

because his battery health on the 750 will stay at around 100% for much, much longer doing it that way.

Plus… What weight saving?
The bigger batteries are typically lighter than their predecessors… ;)
 

PetriKarj

Member
May 16, 2022
20
13
Kasperi94
The chemistry of ebike batteries is the same as in many electronic cars. Charging constantly to 90-100% will shorten the lifespan of the battery. 100% for practical purposes is 4.2v/cell. For nominal 36 volt battery this means 42 volt is 100%. You can measure the voltage from the secondary battery terminals in the charging port.

For this very reason I always charge my Tesla to 70% which is plenty of range to have a longer lasting battery
 

Heems

Member
May 4, 2022
26
147
California, US
I own a Tesla and it's common knowledge for the nickel based batteries it's not good to charge to 100% and let the battery sit there. LFP batteries in contrast want to be charged to 100% all the time. Ultimately it comes down to the chemistry of the batteries used by Giant. Does anyone have any info on that? In it's absence I found Kiwi Giant's recommendation to be a good one to follow.
 

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