A patient came in for an appointment today and said her neighborhood is scheduled for a blackout today. Her charger doesn’t have a built in battery pack.
Most new cars have a USB charging port. If you have an old car, you can always get solar charger. REI has at least two dozen different solar chargers. They’re typically about $50.
All that being said, I have had a number of patients chosen non-rechargeable batteries lately. It made sense for my back packers and touring cyclists. But for anyone with dexterity issues, rechargeable batteries are ideal.