IMR 18490 by
benthiccracker, on Flickr
So I bought these batteries brand new. I marked them and will rotate them. I have a 4 bay charger on the way. If I get a voltmeter/multimeter and check the batteries for over charge 4.2 V and over discharge <3.5 V I should be okay? I will be running them in a extended 9P overbore Zero Res switched with a Malkoff M91. SAFE?
- Brand: Trust Fire 4 bay Charger
- Model: TR-003P4.
- Input 1: 110V-240V 50/60HZ.
- Input2: DC 12V 2A.
- Output: 4.2V 4*500Ma.
- Constant Charge Current: 500MA ±10%.
- Constant Charge Voltage: 4.2V ± 10%.
- Cut-Off Current: 60MA ± 10%。
- Comes with protected function.
- Comes with LED charging indication.
- Size: 141*106*33mm.
- Plug Standard: US Plug.
- Compatible with 10430, 10440, 14500, 16340, 17670, 18500 and 18650 battery.
+/- 10% on the charging range is large. 4.20v +/- 10% = 4.62 v to 3.78 v
So a pair of cells could come off at 4.62 v (OVER CHARGED), or, as low as 3.78 v (Not very charged).
As a rule of thumb, don't buy a charger that is named "Anything"fire.
Because it might set anything on fire.
There are decent chargers that are programmed to charge the cells more safely...and t make the cells last longer.
For example, its great that you'd measure the charge, but what if it IS 4.62 v?
The cell is already damaged proportionally...and if the extended tube is to run multiple cells in series...and the cells come of the charger with that kind of range of charges....how are you going to get matched sets?
The cells will constantly have different histories, different internal resistance, etc.
So, in a perfect world, I'd say just replace the charger with a real one...a Pila IBC (2 Bay), or an Xtar WP6 II (6 Bay), or another one recommended by the guys here who review these things.
It would work better for your application.