Lithium batteries monopolize the residential storage sector currently. LFP batteries outperform NMC batteries for home use due to strong thermal stability and low costs. Lithium-ion energy density has risen by 30% in five years, with cost per kWh falling below USD 120 and lowering popularization barriers. Two technical trends emerge: modular stackable batteries adaptable to various household loads, and intelligent BMS realizing coordinated control of PV, grid and storage. Sodium-ion and flow batteries enter residential trials. Sodium batteries feature excellent low-temperature performance and cheaper raw materials, poised to replace lead-acid batteries and partial lithium batteries in low-end and off-grid markets. Lithium batteries will remain mainstream in five years, while new batteries achieve gradual commercial penetration.