Draining Battery on Giant Explorer +1

[flugelboneman]

I was advised by my dealer to drain battery completely about every 3 months to enhance battery life. I got the battery down to 2%, but it almost refused to go any lower. Is that close enough for jazz?

 

[Mtl_Biker]

I was advised by my dealer to drain battery completely about every 3 months to enhance battery life. I got the battery down to 2%, but it almost refused to go any lower. Is that close enough for jazz?

Wow! That's contrary to what I've always heard about lithium batteries... I've heard that they should not be allowed to run down "completely". I wonder if that's advice from Giant, or maybe from a dealer who doesn't really know battery technology. Do we have any battery experts around here?

 

[Mtl_Biker]

Just found what looks like a great site about prolonging Lithium battery life... https://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries

I'm going through it now, as I'm really going to have to learn about making my new bike's battery last.

 

[flugelboneman]

Yeah, thx for the tip. I went thru this article and am no smarter than I was. I will hope for more input from the website on this. In the meantime will go back to my dealer and confirm what he said.

 

[rich c]

He’s making money on selling new batteries. Woodworking tools that used ni cad batteries had a memory and they had to be fully cycled. Definitely not good for eBike lithium batteries.

 

[Solom01]

If you wanted to degrade the life of a lithium battery it would be hard to come up with a better method than draining it all the way. It's also bad to charge it to 100% but at least there's a reason for that since most ebike battery management systems only balance the cells at the end of the charge. Regardless of what Giant or your dealer says they can't change the chemical properties of lithium batteries.

 

[Slow Rider]

Giant's owner's manual says drain it completely once every three months, here's the exact wording for the 2019:

Discharge the EnergyPak completely by riding the
bicycle after 15 normal charges or at least every 3
months totally before charging the EnergyPak again.
This will increase the lifespan of the EnergyPak.

There isn't really a way to get it down to zero, though, Giant will shut the power off at around 2% before you can do any irreversible damage.

While I don't know if there is anything to gain by running it all the way down, if you were do ride it down to 2% once every three months it's going to be such a minor blip on the life of the battery. But, if you were running the battery down to zero every time, that would significantly impact the life of your battery.

My battery is almost a year old and I've gone down to the 2% a couple of times. Both times battery health recovered to 100%, and the battery lasts as long as it was when it was new.

Best advice you'll find on this site is from Ian Moone:

Life is Short ... Ride it like you Stole it (Or until the juice runs out) !! ??

Other than that, basic advice which would help squeeze a few more cycles out of the battery are:

- don't fully discharge the battery, but if you do run it all the down to 2% don't worry, Giant will shut off the power for you and your battery will charge up fine
- if you do run the battery down to 2%, don't just let it sit in that state. Charge it at least partially as soon as you can.
- try and not let it get below 20%, but if it does, enjoy the ride!
- Charge it to 80-90% whenever possible. Only charge it to 100% if you really need the extra juice
- don't let the battery sit in extreme cold or hot weather
- charge the battery at room temperature, don't charge the battery in extreme cold or hot conditions
- if your going to not ride it for a while, charge it to 60-70%. Giant's charger has a feature to automatically stop the charge at 60%


One thing I did notice is that after charging to 80-90% several times in a row, the battery health indicator starts dropping down, got down to 95% one time. However, once I do a full charge to 100%, battery health recovers to 100% also. My guess is that the battery needs balancing and charging it to 100% does the trick.

 

[flugelboneman]

Thx for your very comprehensive breakdown. Yes it does say run the battery down every 3 months and re charge. Yes I only got it down to 2% and now I know why. I really appreciate your input Slow Rider. And yes, I will continue to ride it like I stole it. One thing I did learn on my trip to discharging the battery down, it happened before I wanted it to and I was then faced with a long up hill climb sans battery. That is when I realized the value of a smaller front sprocket. That is when I also realized what a pig the bike can be without electric assist. I will plan better 3 months from now when I do it again.