If you want to prepare for a power outage the cheap way, buy the same starter battery as in your car. Then buy two battery clamps and something like this:
Cut of the plug, connect the clamps. Now you can load your phone, plug in a car charger for your laptop, even power a router. And anything else that runs on 12V.
You can use it to start your car if the battery in the car has a problem.
Swap it from timr to time with your cars battery to keep both working.
@rudolf if you are going to cut off the plug on the adapter, don't forget to add a fuse. there's a fuse in the plug.
@rudolf Fairly easy and not too expensive to hook up a solar panel and solar charger to keep the battery charged, if you have somewhere to mount it outside. And safety first - typical car batteries can provide enough current to burn up wires and equipment in seconds if you miswire it.
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