I haven't had any problem with the Riobi drills, except for
these 30" stabilizers that I have on the front, which are turning out to not work as well as the
24" Husky ones which I have on the back. I am not generally running down a battery during any raise or lower operation. But I do generally charge them between raising and lowering again.
If you are really concerned, consider this huge
Riobi 9 amp-hour battery for 162 watt-hours of power. I have a pair of those, but also regularly carry several batteries.
The clincher for buying Riobi is that they have a
12 charger which runs off of my solar panels without an inverter, or in the tow vehicle. Few other brands do.