Charging battery outside ideal 15-20c range
- Thread starter confusedcyclist
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OP
OP
confusedcyclist
Veteran
Thanks, there doesn't seem to be any discussion about the how's and why's for the stated ideal charging temperature ranges. As I say, if it's about charging rate, efficiency or achieving the highest possible charged state then I'm not so fussed, I just don't want to unecessarily shorten the useful lifespan, yet lugging a 625 watt battery around gets old fast! That said I'm happy to do it if there is a good reason. I'm already cycling between 20 and 80 % and using a smart timer to bring the battery up to 80% just before I depart for work to ensure the longest service life possible in a bid to reduce cost, both the financial and environmental impact that these batteries can have.
I might write to Bosch to find out.
I might write to Bosch to find out.
OP
OP
confusedcyclist
Veteran
I've automated the process with a TP Link Kasa smart plug. Since my riding tends to be reliably the same day in day out, with only very minor variation, I've found I can set my charger on a schedule. Upon returning home the battery gets plugged in, the battery then has about 2 hours to return to room temperature up after a cold winter ride. Then the smart plug turns itself on after two hours for an hour and half only, to bring it up to about 60% of capacity. It then switches off again until 4am the next day when it finishes charging up to 80%, just before I depart at 6am. Weekends are also built into the schedule, charged to 60% when I return home, then off until Sunday night. Through a bit of trial and error, I'm within a few percentage points of these targets most of the time. With very little in the way of manual effort I should eek out some decent extra life from the battery. If for any reason I need 100% charge, I can set my charger on remotely with a smartphone or google assistant voice command. It's a pity the charger doesn't have this functionality built in, we're paying enough Bosch! I have thought about building my own app to calculate the charging times, but I've found there are too many variables I don't understand yet.
The two things you can do to maximise life are to cycle the battery between 20-80%, and store at around 60%. My system achieves both with nearly no effort. It was all invested up front by taking a few notes on when and how long the charge took to go up up in increments of 10%. If I had time to kill, I could probably work it out with more granular data in 5, 2 or even 1% increments, but what I've got works well enough for now.
The two things you can do to maximise life are to cycle the battery between 20-80%, and store at around 60%. My system achieves both with nearly no effort. It was all invested up front by taking a few notes on when and how long the charge took to go up up in increments of 10%. If I had time to kill, I could probably work it out with more granular data in 5, 2 or even 1% increments, but what I've got works well enough for now.
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