Charge cycles

[Dynz]

Just wondering what min and max voltages you guys would recommend for a 48V 17.5 ah Hailong battery charging cycle.
Until now I've always started charging when battery went down to about 44V and unplugged when it'd been charged to about 52V. This at all reasonable?

 

[Gionnirocket]

Just wondering what min and max voltages you guys would recommend for a 48V 17.5 ah Hailong battery charging cycle.
Until now I've always started charging when battery went down to about 44V and unplugged when it'd been charged to about 52V. This at all reasonable?

A lot depends on your typical ride and how often you'd like to charge.
Keeping the battery around its nominal voltage (48v) is ideal but you need to be practical and enjoy the bike as well.
My typical 20mi ride burns about 2.5v so I keep it between 45v and 50.5v charging every other day. Once in a while I charge fully, especially if I know I have a long ride planned.
Here's a good read: Battery Guide

 

[Bitmugger]

Ok so I've never dealt with Hailong at all, so others can speak to the accuracy of their claims.
They claim to be getting 17.5ah from a 13s5p battery pack. That means 3500ah a cell. So in that bracket you are talking top of the range cells, in reality I think only Samsung offers an 18650 with an actual rated capacity of 3500mah (vs like 3450mah so splitting hairs maybe it's a 17.25ah battery).

Regardless I see no reason for those cells you can't charge the battery pack right to 54.6v and enjoy the extra range (vs 52v).
For low voltage It take my bike down around the same as you, mine cuts off at 43.1v (the bike not the battery) but at 44v I am getting very little useful torque so that's about my limit too.

How are you charging your batteries now given you stop at 52v? Just check it manually or do you have a charging system where you can dial in your voltage?

Update: Just found some specs, the battery is actually a 17ah-17.5ah battery so they could be easily using Sanyo, Panasonic or Samsung. BUT I see they also specifically say "Charge Voltage 54.6V±0.05 V". (max 5A)

 

[Dynz]

How are you charging your batteries now given you stop at 52v? Just check it manually or do you have a charging system where you can dial in your voltage?

Currently I have no other way than to briefly unplug the battery and go into the Battery setting in the SW102 display which shows the voltage. I should add I'm also not sure this is the right way to monitor the charging .

 

[Bitmugger]

I should add, given the chemistry of these cells (for 3500ah name brand cells) I feel they should handle as much as 1000 charge cycles to 54.6v under proper conditions. If you are really putting 1000 charge cycles (like 100,000km) then don't worry about the cost of a fresh battery, it will probably be time for a new bike.

Note: Edited to say "upto 1000" vs "1000+" these cells are all rated around 500cycles I am sure

 

[Gionnirocket]

Currently I have no other way than to briefly unplug the battery and go into the Battery setting in the SW102 display which shows the voltage. I should add I'm also not sure this is the right way to monitor the charging .

Nothing wrong with that at all... and after you gauge how long it takes to add a volt to your pack you can set up a timer on your phone or buy a timed outlet or the smart home type that many here have done.
I took it a bit further.... not because it was necessary, but I like to tinker and built a DIY SMART CHARGER out of a solar charge controller and watt meter that has been working well

 

[Dynz]

Insane!
Am I good to turn the display on with the battery charging or better to unplug first as I have been doing?

 

[Bitmugger]

Insane!
Am I good to turn the display on with the battery charging or better to unplug first as I have been doing?

Turning the display on while charging should be fine

 

[Gordon71]

When I'm done with a ride I charge my battery the morning before my next ride and stop charging when the red light on the charger turns green.

 

[Gionnirocket]

Turning the display on while charging should be fine

I concur.

 

[JES2020]

When I'm done with a ride I charge my battery the morning before my next ride and stop charging when the red light on the charger turns green.

I do the same as you, don't want to keep the battery at full charge for long periods.
When I do a balance charge I leave it on the charger even after the red light goes out as the BMS's only balance the cells at full charge.

I know my balance is working because the voltage goes to 54.9 , instead of the usual 54.6.
I balance once a month in the summer.

 

[Gionnirocket]

For the majority of name brand cells, 54.6v (4.2v/cell) is the recommended maximum full charge voltage.

 

[Gordon71]

I do the same as you, don't want to keep the battery at full charge for long periods.
When I do a balance charge I leave it on the charger even after the red light goes out as the BMS's only balance the cells at full charge.

I know my balance is working because the voltage goes to 54.9 , instead of the usual 54.6.
I balance once a month in the summer.

Interesting about the balancing. I just balanced mine when I bought it last spring and again this spring after it was idle for the winter.