The Baofeng UV-5R is a U/V portable FM transceiver. The battery supplied is labelled BL-5 and rated in this case at 1800mAh.
Supplied charger adapter
Above is the supplied USB adapter to supply power to the CH-5 charger cradle. The adapter is rated at 9V and indeed, it delivers 9.01V no load.
The supplied adapter could not fully charge a battery in 12 hours, reaching a battery voltage of just 8.2V in that time. This represents a loss in battery capacity, about 17% compared to charging to 8.6V (as when the cradle is powered from 10V).
The charger adapter was set aside for this reason and further testing was performed with a 10V bench power supply.
Charger cradle with 10V power supply
It seems common that Baofeng portables use a charger cradle that is powered from nominally 10VDC. The question arises as to the maximum input voltage.
The PCB uses a XT9502 charger chip, and the datasheet for that chip specifies a maximum input voltage of 18V. This should be suitable for charging from an automotive system where voltage may well reach 17V under some charging conditions.
So, it is prudent to label the charger “18.0V Maximum”.
Further, in sourcing a safe standards compliant power supply, it needs to be no more than 18.0V, common 12V supplies should be fine.
I have no seen this one charge at more than 0.32A.
I modified the charger cradle to add a short external cable connected directly to the battery contacts and terminated in an Anderson Power Pole connector for connection to my Westmountain CBA for battery testing. Of course the cable needs labelling to prevent it being used for power input. (This battery can be discharged from the external terminals, keep in mind that shorting those terminals could have serious outcomes.)
The radio is new at the time of writing.
After one full charge – discharge – charge cycle, a discharge test indicates 77% capacity at 0.5C. Chinese battery ratings cannot be trusted.
Comparison with the recent BF-F8HP battery test
Baofeng BF-F8HP battery and charging experience tested a similar battery, also labelled a BL-5 but at 2800mAh.
Some comparisons between the batteries are interesting.
| Label capacity (mAh) | Mass (g) | Measured capacity (mAh) | Capacity (% of rating) |
| 2800 | 78 | 1212 | 43% |
| 1800 | 70 | 1377 | 77% |
It is not a mistake, the 1800mAh battery delivered more capacity than the 2800mAh. Can you trust Chinese battery ratings?
Conclusions
- The supplied USB power converter is not capable of fully charging a battery.
- Battery capacity is short of rating, but by comparison with Chinese battery ratings, this is relatively good.