Eizfan Pro Q4 Intelligent Charger





This is a simple LiIon charger for four cells.



The cardboard box lists some specifications, battery types and features.



The box contains the charger, a mains cable and, manual.



The charger has a mains input socket, it will accept 100-240VAC 50/60Hz according to specifications.



There is not much user interface on this charger, only one led for each slot. It is red while charging and green at other times, except if a totally drained battery is put into the charger, then it will go out.



Specifications are listed on the back.



The slots uses the usual slider construction. They can handle batteries from 29mm to 70.3 mm long, this excludes protected and button top 21700 and a few very long protected xx650 batteries, but everything else will fit in length.






Due to the 1A charge current it is best only to charger high current version of small cells in the charger.
The charger slots are large enough to fit 32650 batteries, but I had trouble getting connection with them.
The charger can handle 70 mm long batteries, inclusive flat top cells.



Measurements

• Discharges with 0.01mA when not connected to power
• Below 0.5 volt the charger will not charge batteries and the led is off
• Between 0.5V and 2.9V it will charge with 75mA
• Above 2.9V full charge current will be used.
• Charges/discharge with less than 0.01mA when battery is full.
• Will restart if battery voltage drops to 4.10V.
• Charge will not restart charging on a nearly full battery after power loss or battery insertion.
• Power consumption when idle without batteries is 0.15 watt

A nice CC/CV charge curve with a termination current around 150mA.





The other slot is similar.






Other types of batteries do not change anything.



With four batteries the charge current drops a bit, this is probably to the temperature inside the charger. I have no idea what happens around 180 minutes, at least the final result is good enough.



M1: 43.8°C, M2: 45.6°C, M3: 44.9°C, M4: 42.0°C, M5: 67.3°C, HS1: 69.9°C



M1: 61.1°C, HS1: 73.2°C



The charger is fairly fast to start, only requiring about 1 second.


Testing with 2830 volt and 4242 volt between mains and low volt side, did not show any safety problems.



Conclusion

It is a simple charger, but for LiIon batteries that can handle 1A charge current it works fine and with acceptable charge speed.



Notes

The charger was supplied by a Eizfan (Efan) for review.

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