Short answer: Charging fast doesn't hurt batteries
Very long answer: read if you want to really understand, otherwise just charge fast and be happy
Charging rates have little to do with cell life. High duration of time spent at high states of charge and high temperature are 99% more damaging to a cell than fast charging most Lithium at 1C, especially Zero batteries because of their very low internal resistance and high power density compared to other electric vehicles. Yet most other electric vehicles can do 80% charge in 20 minutes. The last 20% can take 40 minutes. So when travelling you unplug at 80% and go!
The Zero batteries would probably even better in cycle tests of 80% in 20 minutes than car batteries do with a tapered curve that is about 3C charging to 30% as long as temperature of the cells is 100-105F. The problem with the Zero cells is repeated cycles and heat retention. If you ride highway speeds you will heat the battery, and if you charge fast you heat the battery. So eventually your battery will be sitting at 120F with no way to cool down. Heat is molecular vibration. And the cells can be damaged from this repeated vibration sitting at temperatures above 50C/120F if it happens often.
Best to ride down to only 20% and fast charge only to 80% if you will be travelling and going to perform many charge/discharge cycles in the same day. The battery will heat quicker discharging fast under 20% and it will also heat quicker charging over 80%. It will also heat using just the onboard charger, so use an accessory charger like the Diginow or something with cooling fins and a fan, but that is sealed to moisture and potted.
If you are concerned about fast charging and cell life, unplug your bike at 80% each night first as sitting at 100% is about 20 times worse than fast charging.
In a recent Farasis cell test the 2C charging test for 1000 cycles actually showed better capacity than the same cells performing the 1C charging. Not by much but it was better. Main reason is the 2C test completed quicker and the more important factor to charging was simple time duration and calendar life.
Point is go ahead and use the bike the way you want. Charge up to the 1C limit. If you want to extend your battery life don't even bother charging at night. Carry a fast charger and just charge quickly when you need to.
I had 78,000 miles on my 2012 Zero and never once charged at home overnight. I lived in an off the grid house and had to charge when the sun was on my solar panels. So I just charged from the 300 ChargePoint stations in Orlando.
When I moved to California, I never once charged overnight either. I couldn't. I had no more delta Q's on the bike only Elcon chargers that went straight into the controller and the bike had to be on to charge. I wouldn't want to leave the bike on overnight in my carport, so I just didn't charge at night. Although I never needed to because I had 4 J1772 plugs on my bike to charge extremely fast when ever I needed.
With a full drain, and full charge test using 5 significant figures from chargepoint after 75,000 miles I had lost less than 1% of my total capacity. A week after running that test I rode 300 miles at 70 mph from Scotts Valley to northern California.
http://insideevs.com/electric-terry-hershner-rides-300-miles-on-zero-motorcycle-on-one-charge/My batteries were as strong as they were new after 78,000 miles of only fast charging. Think about that...
But my bike sat overnight and when I wasn't using it at what ever I arrived home with. Probably 30-50% SOC is where it sat most of the time when I wasn't using it.
Now no one needs to worry about unplugging your bike at night. But don't worry about fast charging either then. Just use your bike so it makes you happy. The best way to get the most mileage out of your battery, ride it a lot and fast charge it and ride it more! That bike will have the potential to have many more lifetime miles on it than the one that doesn't fast charge. Make sense?
I'm hoping Brandon will have an app for the new Diginow superchargers soon so you can set voltage on the app to be like 110 volts and so you can plug in at night and the bike will automatically stop charging at 80% so you don't have to think about it. You can plug back in the morning if you want to top off to 100%, or just don't worry about it if you have a supercharger. You can always fill up fast if you need to.
The only negative thing for batteries in regards to fast charging is low temperature. Always ride your bike first and heat the batteries to at least 70F/20C if you are going to fast charge. Batteries don't even like the onboard charger when just above freezing. So if you live in a cold climate, you can store your bike in the cold in the winter when you aren't riding it, that's fine an actually better for the batteries to be stored in the cold for long term storage, but if you ride it each day, keep it in a heated garage or in the kitchen or living room overnight in winter if you will be using the fast chargers the next day.
Also it's best not to fast charge to 100% SOC. I'm guilty and did it many times in the 78,000 miles so it didn't do anything drastic, but you are probably better off charging really fast to 80%, then unplugging and just stopping a little sooner between charging stations.
One day algorithms on the supercharger will have all this programmed into it to maximize battery life and you can make adjustments from an app. I know there is work being done on that now from a few developers on the Diginow supercharger messenger boards
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Topic: SLOW charging vs FAST charging and battery life (Read 6458 times)