Portable power station that is easy to carry. Good for powering laptops, portable fridges, lights, fans, phones and other electrical devices that draw less that 600 watts. Around 2,500 charge cycles before the battery reduces to 80% capacity. Should easily last 10-20 years depending on usage. Decent price for who need it now but was lower once or twice before. I own one and can vouch for quality. Cab be charged via AC, car (DC) and solar panels (MPPT built in).
You can make one yourself for cheaper but this is about convenience and portability.
It's only a 268.8Wh model, so its not really that great for fridges.