Miboxer C8 charger: unable to set battery type to Li-Ion

dmenezes

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Hello everyone,

Having a problem with MiBoxer C8 charger: I overdischarged a LG HE4 18650 battery down to about 1.2V (I know, not recommended -- stupid piece of electronics being powered by it had no auto-poweroff, and was left on long after the battery drained), and when I insert it on the charger, it's recognized as a NiCD/NiMH battery (due to the voltage, I imagine).

When I try to set the battery type to Li-Ion 4.2V (following the manual: by long-pressing the [MODE] button, followed by short presses), the battery type doesn't change: it keeps displaying "NiCd/NiMH".

The weird thing is, the manual explicitly says this charger can recharge and even restore overdischarged Li-Ion batteries!

What am I missing?

Thanks in advance,
-- Durval.
 

TinderBox (UK)

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"restore overdischarged Li-Ion batteries" the manual is poorly written.

This is for protected Li-Ion cells that have a voltage cutout, say the voltage drops to 2.5v/3.0 the cut-out will activate and if you check the cell with a DMM it will show zero volts or a open circuit.

When you put this battery in the charger, The charger uses an high voltage to reset the protection circuit and the cell will start working normally again and start charging.

Why the charger discharged on Li-Ion to 1.2v should not happen, But if the cell has an low voltage say under 1.8v the charger might think it is an NiMh and discharge too far.

Any Li-Ion cells that you discharge below 2.5v should be binned/recycled as they can be dangerous, Also a lot of people will return Li-Ion cells they have ordered if they measure 3.0v or under.
 
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dmenezes

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Messages
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Currently in Chile.
Thanks for the explanation, @TinderBox (UK); more, below:

"restore overdischarged Li-Ion batteries" the manual is poorly written.

This is for protected Li-Ion cells that have a voltage cutout, say the voltage drops to 2.5v/3.0 the cut-out will activate and if you check the cell with a DMM it will show zero volts or a open circuit.

When you put this battery in the charger, The charger uses an high voltage to reset the protection circuit and the cell will start working normally again and start charging.

Weird. If the battery shows zero volts ie an open circuit, how can the charger detect it in order to "know" it has to send the high voltage to reset it?


Why the charger discharged on Li-Ion to 1.2v should not happen, But if the cell has an low voltage say under 1.8v the charger might think it is an NiMh and discharge too far.

Any Li-Ion cells that you discharge below 2.5v should be binned/recycled as they can be dangerous, Also a lot of people will return Li-Ion cells they have ordered if they measure 3.0v or under.

Thanks for the explanation and heads-up. The battery in question seems to be operating normally...

But, what I would really like would be a way to set the charger manually to LiIon (or any other setting) independently of what it thinks the battery is. Does anyone know how this can be done, or why it can't?

Thanks in advance,
-- Durval.
 

dmenezes

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Joined
Oct 23, 2020
Messages
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Location
Currently in Chile.
It says in the manual you can select the battery type using the mode button.

Tried that already, as per my original post (first one in this topic):

When I try to set the battery type to Li-Ion 4.2V (following the manual: by long-pressing the [MODE] button, followed by short presses), the battery type doesn't change: it keeps displaying "NiCd/NiMH".

You can download the manual in the link below.

http://www.miboxer.com/eng/down.html?filepath=13

Thanks for the link, but I got the manual already, as stated.

If anyone has any further ideas and/or info, I'd be grateful.

Thanks in advance,
-- Durval.
 
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