I have used this charger in the vehicle to keep the HT charged when on the road and it works great.

I have used this to charge from a portable backpack solar charger successfully

While a cable that would plug directly into the battery would be simpler to use (without requiring the charging dock), this USB Smart Charger cable that plugs into the charging dock does allow me to charge my BaoFeng BF-F8HP HT radio's battery from a USB port in my car or from any other powered USB port (as long as I have my Battery Charging Dock to plug it into).

I got this USB Transformer Cable for my btech usb smart charger for my radio so when I go hiking I can charge

Works as you would expect, charges via USB port, I like this for off grid applications, charging from solar