Hobby charger question

[smopoim86]

I bought the Bantam E-station BC8 from neumotors when it was on sale for 105 shipped. I have been playing with it a bit today and noticed the cutoff voltages for each cell chemistry. "LiPo 4.2v, LiIo 4.1v, LiFe 3.6v" Why is LiIo at 4.1 instead of 4.2? As far as i can tell there is no way to change the finish value. Would it be safe to charge LiIo using the LiPo program so they finish to 4.2v? I'm enjoying being able to charge a set of aw2600 in a little over an hour instead of half a day on the wf139.

~Daniel

 

[SilverFox]

Hello Daniel,

Many hobby chargers are set up the same way.

It is OK to charge most modern Li-Ion cells using the Li-Po setting.

On the other hand, you will get extended cycle life if you limit the maximum charge to 4.1 volts.

Your choice...

Tom

 

[smopoim86]

Thanks, that's what i figured. I didn't know if the actual charging algorithm might be different. I'll probably leave it on the LiIo option since it should add a considerable about of life to the cells. It should only be a couple hundred mah right? (maybe less)

 

[clintb]

Thanks, that's what i figured. I didn't know if the actual charging algorithm might be different. I'll probably leave it on the LiIo option since it should add a considerable about of life to the cells. It should only be a couple hundred mah right? (maybe less)

Same charging algorithm; CC/CV (Constant Current/Constant Voltage). Once it gets to a certain voltage, the current is lowered considerably, and it's all Voltage from there on out, kinda like a top-off charge.

Check page 7 of the manual for changing termination voltages, it's under the "User Set" menu.

 

[smopoim86]

Check page 7 of the manual for changing termination voltages, it's under the "User Set" menu.

All it allows is to select the batt chemistry. I'm probably just going to leave it cuttting off at 4.1. It's not going to hurt anything.

 

[SilverFox]

Hello Daniel,

The difference between 4.2 volts and 4.1 volts is about 10% of the total capacity.

Tom

 

[Patriot]

Many hobby chargers don't even differentiate between li-po and li-ion and you just select that mode (li-po/li-ion) for either type. If maximum capacity is more important you can always use the li-po setting. If battery lifespan is more important you can keep using the li-ion setting.

 

[smopoim86]

Thanks guys, I figured what everyone has said was the case but thought it was worth checking. Is there any testing that shows the difference in lifespan from charging to a reduced voltage?

 

[SilverFox]

Hello Daniel,

When cell phones when from using NiMh chemistry to Li-Ion chemistry there was a lot of testing done showing the improvement in cycle life by limiting the charge to 4.1 volts. I can't seem to locate this data now. Over the years it may have dropped off the net.

I guess you will have to do your own searching. If you happen to run across this testing, post a link for us.

Tom