For some time I am looking at a home built UPS to power my entire house; not buying an UPS, but building an UPS from a few packs of LiFePO4 batteries (probably

For some time I am looking at a home built UPS to power my entire house; not buying an UPS, but building an UPS from a few packs of LiFePO4 batteries (probably in series to 48V) and an inverter. This kind of setup can be built with regular lead acid batteries too, very cheap, but the battery life is a lot worse than LiFePO4. A 4kW inverter can power my entire house, I live in Europe and we don't use dryers here, I think they are the biggest electrical consumer in a typical US house. The utility link is limited to 4.5kW anyways, so I don't lose much. The whole point is I can easily expand in the future to charge from a solar panel array; solar panels are cheaper and cheaper, the biggest cost is the batteries and installation. Until then, the batteries can be charged from the utility company and the efficiency is close to an APC Smart UPS.