Trance E battery health

Alex

New Member
Jan 25, 2019
5
2
SF Bay Area
Bought trance e 2 a month ago. I have done about 250 miles on it and mainly using eco plus mode on fairly flat paved/gravel trails as of now. I noticed my battery health now is 97% with 4 cycles of charge. If battery health continue in this pace it will reach 80% in less then a year. I do follow instructions on how to care, store and charge battery. Is it normal? What is your experience?
 

MattyB

E*POWAH Elite World Champion
Jul 11, 2018
1,266
1,279
Herts, UK
I keep bike inside as well and charge it after every ride. Will check with LBS what could be the issue.
Storing at full charge reduces cycle life and effective capacity over time. You don’t need to charge it after the ride either unless the indicated capacity is below say 30% (lithium ion batteries have very low rates of self discharge so this is perfectly safe). Best storage state between rides is 30-70% (the so-called “Goldilocks zone;)); don’t charge to 100% unless you are certain you will be going out within 24hrs.

More threads on this topic...

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

57 Reaction

Member
May 27, 2019
73
56
United Kingdom
OK thanks, that's how I am checking mine, just wondered if there was some other more sophisticated method.

Mine has done 1200 miles, 45 cycles over 5 months and still shows 100%.

I fully charge after every ride so it's ready to go next time.
 

KuRi

Active member
May 30, 2019
376
185
Spain
I think I had some problems with temperature last charge... I was at 40ºC and it stopped the charge at 80%. Then I went for a ride, charge again, it fully charged, but it lost 2% of health :(

The bike is only 2 weeks old, but because of the stupid 20% over the first year warranty policy I don't think they will replace mine :(
 

MattyB

E*POWAH Elite World Champion
Jul 11, 2018
1,266
1,279
Herts, UK
All these "battery health" ratings are just nonsense - unless you know exactly how they are calculated they are meaningless. They may allow a rough comparison from battery to battery, but if you want to know the actual performance now you'd need much more specialist kit to do a controlled discharge:charge cycle.
 

KuRi

Active member
May 30, 2019
376
185
Spain
I read somewhere that some cells die and that's how you get the battery health decreased. Mine had a hardware problem because it stopped charging at 80%, so indeed some of my cells have died :(
 

57 Reaction

Member
May 27, 2019
73
56
United Kingdom
All these "battery health" ratings are just nonsense - unless you know exactly how they are calculated they are meaningless. They may allow a rough comparison from battery to battery, but if you want to know the actual performance now you'd need much more specialist kit to do a controlled discharge:charge cycle.

That's kinda what I was eluding to when I asked if people were using something more sophisticated than the app.

I used to fly RC planes + helis and had lithium polymer (lipo) batteries to power them, EBikes use lithium ion (lion) batteries.

We had very smart chargers that monitored and balanced individual cells during charging to avoid overheating and fire risks associated with lipo batteries.
It was possible to see how much charge a battery actually took to assess it's health (capacity).

Lion batteries are generally considered to be much safer than lipo batteries.:)
 

MattyB

E*POWAH Elite World Champion
Jul 11, 2018
1,266
1,279
Herts, UK
...I used to fly RC planes + helis and had lithium polymer (lipo) batteries to power them, EBikes use lithium ion (lion) batteries.

We had very smart chargers that monitored and balanced individual cells during charging to avoid overheating and fire risks associated with lipo batteries.
It was possible to see how much charge a battery actually took to assess it's health (capacity).

Lion batteries are generally considered to be much safer than lipo batteries.:)
Sorry, but there are two inaccuracies in the above...
  • Lithium ion is the overall battery chemistry "family"; both Lipos and LiFe (Lithium Iron PO4 technically; this is the cell chemistry in almost all ebike batteries) are part of that overall group. As you say LiFe is safer, primarily because it does not have the gel layer through which dendrites tend to form more readily. These can cause internal shorts and also increase internal resistance (IR) over time, reducing the ability of the pack to deliver high currents.
  • Seeing how much charge a battery will take is not on its own an effective measure of battery health; it's only one component. You are correct that if it's awful the battery is probably dead, but equally I have seen plenty of packs of different chemistries that will take a charge but won't perform during discharge. Discharge capacity at different loadings and IR (both of which are inter-related) are far better indicators of pack health, but there are other factors too (like the temp and terrain) which can influence the real world performance drastically.
PS - Yes, I too have >30 years experience in RC, the last 15 or so flying electric powered aircraft ;).
 
Last edited:

57 Reaction

Member
May 27, 2019
73
56
United Kingdom
Sorry, but there are two inaccuracies in the above...
  • Lithium ion is the overall battery chemistry "family"; both Lipos and LiFe (Lithium Iron PO4 technically; this is the cell chemistry in almost all ebike batteries) are part of that overall group. As you say LiFe is safer, primarily because it does not have the gel layer through which dendrites tend to form more readily. These can cause internal shorts and also increase internal resistance (IR) over time, reducing the ability of the pack to deliver high currents.
  • Seeing how much charge a battery will take is not on its own an effective measure of battery health; it's only one component. You are correct that if it's awful the battery is probably dead, but equally I have seen plenty of packs of different chemistries that will take a charge but won't perform during discharge. Discharge capacity at different loadings and IR (both of which are inter-related) are far better indicators of pack health, but there are other factors too (like the temp and terrain) which can influence the real world performance drastically.
PS - Yes, I too have >30 years experience in RC, the last 15 or so flying electric powered aircraft ;).

Agree with your fuller explanation.

I was trying to keep it simple as I was trying not to turn bike forum into a chemistry lesson.

Happy and safe landings ......both sorts.
?‍♂️
 

Alex

New Member
Jan 25, 2019
5
2
SF Bay Area
Hi Alex, what LBS did tell?

Mine is 2 cycles, 98%...
@KuRi LBS did not find any issues with battery and told me to keep an eye on it and come back later if battery health keeps dropping. The battery health was not dropping beyond 97% when it had 10 cycles (not bad). Then one day bike reported an error when I powered it on. Error was indicating battery pack issue. I brought bike back to LBS and Giant replaced both battery and charger within few days.
 

Alex

New Member
Jan 25, 2019
5
2
SF Bay Area
OK thanks, that's how I am checking mine, just wondered if there was some other more sophisticated method.

Mine has done 1200 miles, 45 cycles over 5 months and still shows 100%.

I fully charge after every ride so it's ready to go next time.
@57 Reaction does app show how many total miles did you do on your bike? Or you need to record each ride and sum it up or estimate manually?
 

Hex

Member
Jun 16, 2019
4
4
Poland
My advice - just try to not overheat it. High temps are deadly for LI not the actual SOC.
The BMS or built in charger thermistor should prevent it from damage, but remeber lithium ion batts don't need oxygen to burn.
 
Last edited:

KuRi

Active member
May 30, 2019
376
185
Spain
I checked it again today, and it is at 96% after 3 months and 16 cycles. I think it is too low so I have an appointment with the LBS on tuesday.
 

Pukmeister

Active member
Jul 18, 2019
283
263
Fareham
Just had the first free service done on my Trance E+2, no issues at all. I stuck a 60% holding charge in it so they could update firmware etc, I haven't ridden for a couple of weeks due to a chest infection.
 

Evolution Stu

E*POWAH Master
Subscriber
Jun 30, 2019
455
447
Blackpool. U.K.
The key to good battery life on these bikes is to use the storage charge button if you don’t NEED 100% capacity.

You can charge it many times to 60% and do far less damage to the cells than 1x 100% charge due to the way the battery is over volted to get max capacity.

That’s what the button is for, but Giant have done nothing about explaining WHY it’s there to the masses.
 

Hooston76

New Member
Oct 4, 2019
9
2
Cape Town
Mine dropped to 96% after a couple of months.....now at 37 charge cycles its at 97%......I wouldn't worry too much if it drops up to 5%
Hi I am looking at buying a used Trance E+2 and the diagnostic report shows capacity at 96%, attached is the report is this a good buy, the price is really good for a 2019 model with 700km.

9BBB127E-3782-4345-B021-439B3F444BA0.png
 

KuRi

Active member
May 30, 2019
376
185
Spain
That report is pretty normal. I algo got 96% after 10 cycles and it has remained at that % after 40 cycles. It is weird that shows no real usage of the drive modes (off 100%???).

When I buy a used bike I am more worried about mechanical issues than electronic, because this motor is pretty solid.

Good Luck!
 
Last edited:

Hooston76

New Member
Oct 4, 2019
9
2
Cape Town
That report is pretty normal. I algo got 96% after 10 cycles and it has remained at that % after 40 cycles. It is wierd that shows no real usage of the drive modes (off 100%???).

When I buy a used bike I am more worried about mechanical issues than electronic, because this motor is pretty solid.

Good Luck!
Thank you KuRi, according to the bike shop that tested it they say that the control was changed. Thanks for the feedback. The price is too good to miss out on for this bike.
 

KuRi

Active member
May 30, 2019
376
185
Spain
I think you need to connect to the bike directly. I tried getting all bluetooth messages from the control and all I got is the same you get on the app :(
 

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