I was waiting for the industrial response to battery powered vehicles. Each vehicle is bought with a set of two batteries. They are swapped out as the preferred charging method. One is charging while the other is operating. They are slid in and out with a hoist at the charging station next to a gantry. Batteries don’t get short cycled that way.
Reminds me of how you can swap your empty propane bottles for full ones. Of course, if you’re not careful they will give you old, dented, rusted bottles for your pristine, new ones.
At least with the bottles you can tell what you’re getting with a glance...
Salt and rust-rot ruined it by 1982.
The tanks should be pressure tested when replacing the OLD valve with a NEW Valve. If the tank is not leaking then slap a coat of new white paint on it to go with the NEW Valve.
Any reputable Propane Company will do this. The simple way to know if your Tank is safe and up to Date is by checking the Valve for the triple valve handle.