i haven’t received the nitecore d4 charger yet but i have a programmable r/c battery charger. it can charge from .5 amps to 5 amps. is it OK to charge 1 battery at a time at .5 amps? or is that too high and i need to charge 2 at a time? does anyone have a wiring diagram where i can build a balancing charging rig to charge 2 cells at at time? my charger has a plus, negative, and balance port.
Hey mate .5 amps (500mah) is fine you can go a little higher if you need to. The nitecore charger charges at 750mah when only using slot 1 and 3. I am not sure how you can build a rig but you could get a battery holder one that has terminals and hook your hobby charger up to The terminals so you can charge more then one battery at once. I think you only need to balance batteries if they are in series but im not sure about that one. You would need a parallel terminal set up to charge more then one at once without needing to balance.
This post has some charging cradle ideas Hobby Charger and LiIon charging cradles
Parallel charging is recommended as it is works well and can be much faster than balance charging.
see here for wiring diagrams for balance charging R/C Calculations
and here for a good thread on parallel charging with actual measurements of initial current flows between cells of different voltages: Li-Ion Parallel Charging | Candle Power Flashlight Forum
and here is an R/C site that goes into parallel charging in great deplh: https://sites.google.com/site/tjinguytech/charging-how-tos/parallel-charging
A balance charger is my preferred charger as it has a perfect charging algorithm, and never exceeds 4.2 volts, and after reading most of HKJs charger tests, this is a good thing.
For 4.30 and 4.35 volt Li-ions look at this thread: eBay adjustable CC/CV module for 4.3v cell charging?
i’m going to discharge the cells using the charger. what’s a safe rate to discharge at? i can discharge at 0.1 to 1.0 amps. after that i’ll peak charge the cell to see total capacity.
You should charge the cell first, then the discharge will more accurately tell you the capacity.
Most hobby chargers cut off Li-ion discharge at 3.0 volts.
To compare your cells capacity to the manufacturers, you should examine the specs for that cell, and follow the manufacturers capacity test as closely as possible. Many manufacturers do a discharge test at .2C, and discharge to below 3.0 volts.
As most flashlights start getting dim at 3.2 volts or so unless they have a boost driver, I think the 3.0 volt limit is a more practical test of usable capacity.