Charger Panasonic BQ-CC16





Panasonic has a line of NiMH chargers, some are fast and smart, others dumb. This one here is a fast and smart charger.



I got the charger in a blister pack. In addition to the charger there was eneloop pro cells.



The makes the total contents: The charger, 4 eneloop pro cells and a instruction sheet in many languages.



The charger is designed with a US power plug but includes a EU plug. The EU plug requires tools to remove.



With the US plug the plug can be folded into the charger, but not with the EU plug.



The charger has four hidden leds to show when it is charging. With only two batteries in the charger only two leds will be on.
This charger does not use the typical red/green led, but only green led and green means charging.



The charger has the typically two level slots used for AA and AAA batteries.



The AAA batteries are not locked very hard into place.









Measurements charger

• Very low current draw (<1uA) from batteries when not powered
• Below 1 volt the current is pulsing up to 0.5A
• Above 1 volt the full charge current is used.
• When charge is finished the charger will charge with less than 0.1mA.
• Charge will restart charging after power loss, or battery insertion.
• Steady green light is charging.

The charge looks like voltage termination, but it does fill the battery (Temperature increases) and supplement with a two hour top-off charge.





All channels looks the same.



The XX also looks the same.



The pro cell (The one supplied with the charger) uses a -dv/dt termination and has a rather large temperature increase.



I wonder what the powerex terminates on, it is missing the temperature increase that signals a full cell.
But the charger has nearly filled the cell, not much capacity is missing.



The AAA must be a voltage termination. The charger current is reduced for this smaller cell.



With the full eneloop it looks like a -dv/dt termination and a top-off charge.



With 4 cells in the charger the current is reduced.



M1: 36,5°C, M2: 40,4°C, M3: 42,8°C, M4: 41,7°C, M5: 53,9°C, M6: 30,5°C, HS1: 60,2°C
The temperature is fairly normal for this type of compact charger.



M1: 36,1°C, M2: 40,1°C, M3: 43,3°C, M4: 41,8°C, M5: 50,5°C, HS1: 53,9°C



The charger needs about 3 seconds to start.



The charger is using pulsing current. The current in the pulses is about 2.2A and is independent of battery voltage.



With 3 or 4 batteries in the charger the pulse pattern is changed. The pulse is always the same but the charger will use 2 or 4 phases depending on the number of batteries.



With AAA the current is reduced, but the pulse pattern is the same.


Testing the mains transformer with 2500 volt and 5000 volt between mains and low volt side, did not show any safety problems.



Conclusion

The charger is very good at filling the eneloop batteries. The two hour top off charge helps filling batteries if the charge terminates slightly early. No trickle charge is an advantage for LSD cells.
I would have preferred a lower charge current for more time, instead of the high current pulses, the pulses may give problems with some old cells.

I believe this is a good NiMH charger.



Notes

Here is an explanation on how I did the above charge curves: How do I test a charger