Besides the car battery, if you value your computer equipment, you might want to have a UPS (uninterruptible power supply). In normal use, it’s plugged into a wall outlet and its sizeable lead acid battery is always close to fully charged when there’s electricity in your house circuit. UPSs are also made to double as surge suppressors and line conditioning devices (protect against moderate over- or undervoltage as well as spikes). Solid State Disks are a lot more susceptible to power mishaps than older mechanical magnetic hard drives. So, if you’re running a recent computer with an SSD inside and it’s not a battery-powered laptop or tablet, it ought to be run off a UPS. Our UPSs have USB ports on them through which one can recharge phones, tablets, hearing aids, etc.
And power banks and efficient, foldable solar panels are a lot cheaper than they used to be. We have two cars, two UPSs, and a very large collapsible solar panel plus a very large power bank. So, if anything comes along that can totally destroy all these power resources, we’ll be lucky if we live through such a disaster ourselves and just thankful to still be alive.
And within a year I hope to own a Ford F-150 Lightning with the “Power-Your-House” option. Its battery holds 131 kWhr of electricity, enough to power my house for 3 to 10 days depending on how I ration power use, so I doubt I’m going to have trouble charging any rechargeable hearing aids. It will be hooked into our circuit panel in the garage when its parked at home.
I’d say the limits of rechargeability are more in people’s imaginations than in reality. Yeah, the electricity is going to be lost and there go the rechargeables and anything that could recharge them, but the house and the flood and winds didn’t wash away your supply of disposable batteries and never will - you sleep with them strapped to your chest?
BTW, a principal reason for wanting to buy the Ford F-150 EV is not the desire to go green, etc. (although that’s a factor). It’s just that electricity is so relatively unreliable in the State of Texas, I don’t like living in the dark and freezing for days on end as we had to do after the great Valentine’s Day freeze-out in 2021. At least we’ll be able to have light throughout the house and run a few space heaters where we need them if the same thing occurs again. It was 9 deg F outside. The temp inside our house fell to 44 deg F. My daughter’s house in Austin was something like 36 deg F and they pitched a tent in their living room to have a bit more warmth inside the tent. Power outages in Texas are a regular occurrence. So advance preparation is helpful. Whether or not you want to keep rechargeable HA’s running.