Stop and restart NiMH Charge?

[kurtz49]

I have a new Duratrax Onyx 5000mah NiMH battery and a Hyperion EOS0606i AC/DC Balance Charger.

I started charging the pack last night at 1amp but it did not finish before I went to bed, only got to about 2000mah. My question is if I start charging it again this morning will my charger automatically stop charging when it has added an additional 3000mah? Or will it try to get to a full 5000 mah (thus over charging it), and I will need to manually stop charging it at 3000mah?

Sorry for being a noob and thanks in advance for the help!

[Greatscott]

You should be able to push that battery to at least 3 amps, I'm betting to 5 amps to charge. Setting that battery for 1 amp is spoon feeding it.

I'd cycle the battery before you put it back on the charger. Some of the battery/charger gurus might have a better way to handle it...

[reden]

My experience with NIMH's are slow charge cycle for first couple of times.
Slow charge at 0.5a for about 12HRs then only can you fast charge
It's like training your muscles.
Slow at first then later go faster.
I would also not go over say 3A charge for 5AH batteries.
My preference is half charge rate of the capacity.

[kurtz49]

I read that the first time you should slow charge...but after that I was going to do a 1C charge or 5amps. I already started re-charging it so hopefully it will be okay. Worst case I learn my lesson!

[kurtz49]

Originally Posted by reden

My experience with NIMH's are slow charge cycle for first couple of times.
Slow charge at 0.5a for about 12HRs then only can you fast charge
It's like training your muscles.
Slow at first then later go faster.
I would also not go over say 3A charge for 5AH batteries.
My preference is half charge rate of the capacity.

Good advice...thanks.

[JohnRobHolmes]

Be wary with the 0606i, if you charge them too slowly it won't terminate the charge properly and just keep feeding them unless the mah cutoff is set.

.5a for the first 5 charges, and 3 to 5a after that is pretty good advice for hobby grade nimh of that capacity.

[kurtz49]

Thanks for the advice JRH. Sounds like I have my marching orders for the first few charges!

[JohnRobHolmes]

With Nimh if you charge them faster you will get better punch, but if you charge them slower you will get longer runtimes. Just some tips from an old nimh junkie. I haven't touched that chemistry for a few years now!

[reden]

Thanks John.
Makes sence if one is flying a F3J glider.
Lots of fellow pilots lost glider due to over charging.

All the cells disharges ok untill ones drop drasticly in voltage.
Not a problem in crawlers but costly in gliders.

BTW. I just converted to LIPO's.
First squeeze of the throttle and Bully was over the horizon!

Volt up! Gear down!

[Charlie-III]

reden, typically a NiCD/NiMH charger will stop charging when the voltage/charge curves meet preprogrammed values. Thus, you can charge a pack from any starting point and the charge should stop the charge when the pack is full.

Another old trick is to fully charge packs the night before needed, then do 1-2 top-offs just before putting them in your vehicle. This warms up the packs internally and they give out a little better punch when you use them.
Warm is good, hot is not.

[reden]

Fast charge also give a temperature rise.
Too fast and a cell might go bust.
The Delta V is what stops the charge in most chargers.
Remember, cells in gliders reffered to are muck smaller than sub C cells.

Most sub C's can take quite a charge.
Unlike the old NICAD's that could be abused quite a lot.

[bob1961]

Originally Posted by JohnRobHolmes

Be wary with the 0606i, if you charge them too slowly it won't terminate the charge properly and just keep feeding them unless the mah cutoff is set.

there is a mah cut off on this charger john, where do i set it....i have that charger and never seen anything in the book or the screen asking/saying to do so......bob

....

[entropy]

I have an Onyx 220, and charge at 4A. Seems to be a good compromise.
I also am nice to new batts, and charge them slowly at first.