Li-ion battery pack - 3rd party 1200mAh Short life span
- The 3rd party knockoff Li-ion battery pack NB-2LH that I got in April
worked fine until last week. The pack will not take a long charge
from the Canon CB-2LW charger; the charger just shows orange on the
indicator for a few mins. and then it goes green to indicate that the
pack is charged (which is false). I paid a whopping whole $7.97 +$3
shippping for the battery so I didn't hesitate to crack open the
I found the 2 cells each had uneven voltages so I bypassed the safety
circuit that's wedged between the 2 cells; it's purpose is to prevent
overcharging so be careful not to overheat them too. The bypass was
no more than just connecting the + and - poles with a different
charger. I used the discharge function on my charger to take the 2
cells down and then recharge them all the way back up. When the
charging cycle was complete, the Li-ion battery pack was back to
normal now - each cell measured 3.7-4.0volts X 2 = 7.4-8.0volts final.
Don't know how long this fix will last so I'll report back later. My
recommendation is to always have one real Canon Li-ion pack that came
with the camera and the 3rd party cheapies as backup. Use the Canon
battery on those dives that really count but remember it has only
720mAh capacity. It was a gamble for me even after new life was
brought back to the Li-ion pack; on average I shoot 150-200 images
underwater. I plan to drill holes in the pack casing to access the + &
- poles of each cell so I can check them to see if one is way below
the other by remeasuring with a volt meter.
The Canon charger is designed to quit charging the pack when it
detects that pack is up to the 7.2volts. With the 3rd party Li-ion
packs, it looks like the charger can be fooled by the one cell being
at very high charged capacity and the other being too low but still
measuring enough to show that the combination of the 2 cells the 7.2volts.
This has been what I've experienced with the Li-ion packs, if you've
had different, please do post your experience(s).