wptski
Flashlight Enthusiast
Just purchased an accessory LED light for a camcorder which comes with two Li-Ion 7.2V 2200mA batteries which are wired in parallel. It comes with a wall charger for one battery but the unit has a so-called charging port marked 7.4-14.8V DC and nothing mentioned as to the current rating needed.
I waiting on a dual-bay charger for convenience but charged them using a linear power supply. I had the batteries inserted and plugged in a 12V 500mA wall wart. I noticed it got pretty warm after a short use and unplugged it.
I rigged up a test with a two channel scope to read voltage and current. One thing is that it draws around 1400mA which is why my wall wart got warm.
I had fully charged batteries connected with various jumper wires. Unit OFF, a 12V 1500mA wall wart plugged in applies around 15V which is the no load voltage of wall wart to the batteries! I only did this for a few seconds of-course. It was only drawing 30mA at this time. I wonder if somebody not knowing about this left it charging dead batteries what would happen??? KaBoom in the night?
I did read one review on Amazon where the user stated that a battery blew up in his office and burned his carpeting.
I waiting on a dual-bay charger for convenience but charged them using a linear power supply. I had the batteries inserted and plugged in a 12V 500mA wall wart. I noticed it got pretty warm after a short use and unplugged it.
I rigged up a test with a two channel scope to read voltage and current. One thing is that it draws around 1400mA which is why my wall wart got warm.
I had fully charged batteries connected with various jumper wires. Unit OFF, a 12V 1500mA wall wart plugged in applies around 15V which is the no load voltage of wall wart to the batteries! I only did this for a few seconds of-course. It was only drawing 30mA at this time. I wonder if somebody not knowing about this left it charging dead batteries what would happen??? KaBoom in the night?
I did read one review on Amazon where the user stated that a battery blew up in his office and burned his carpeting.