Charger Xtar MP1



This charger is a small single 18650 charger.



The charger is powered from a mini usb connector and only supplied with an usb cable.





As extras it is possible to get both car adapter and universal voltage (100-240VAC 50/60Hz) mains adapter.





The charger can handle 70 mm long batteries, including flat top cells.



Measurements

Below 2.8 volt the charger will charger with 60-70mA.
Between 2.8 volt and 4.18 volt the charger is applying regular charge current (See curve below).
At about 4.18 volt 90 mA charger current the led will change to green, but the charger will continue to charger until the current is below 33 mA.
If the voltage goes below 4.07 volt the charger will start charging again, but the led will stay green.
If the voltage goes below 4 volt the led changes to red.
When charger is disconnected from power, but with a battery in, it will draw below 35uA from the battery.




The charge curve shows a approximation to a CC/CV charger, but it starts reducing charger current at 4 volt, instead of 4.2 volt, this increases the charge time. It will also say "end of charge" before the battery is fully charged, this makes it possible to get a nearly full (95%) battery "fast", but there is missing some visual indication of when the battery is fully charged.



A new LiIon cell with a low internal resistance. The charger say ready after about 7 hours, but does first stop charging after about 9 hours.



My old RCR123 IMR cell.



Conclusion

The charger has a CC/CV charge profile, but not optimized for fast charging. The charge current is low enough to handle many battery sizes, but there are no spacers included. This charger, with its small size, is fine for a travel charger and for single cell use, but for frequently charging a couple of cells I would prefer a faster charger with more channels.



Notes

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

The charger was supplied by XTAR for a review.