For storing your lithium-ion batteries like the Xiaomi BM20 and 804066, it’s best to keep them at 3.6 to 3.8V and check them every 3-6 months, especially since your home is quite warm. Recharge if they drop below 3.6V. For your Ni-MH AA batteries, don’t store them empty; keep them charged to about 50-70% and check every 3-6 months too. If you store them fully charged, make sure to recharge them if needed. High temperatures can be tough on batteries, so try to store them in the coolest spot you can find.