Early household batteries only served as emergency power with simple business modes. Global power market reforms reshape commercial models and create three profit channels: peak-valley arbitrage (charging at off-peak low prices and discharging at peak high prices to cut electricity bills), PV self-consumption (storing surplus rooftop solar power to avoid revenue loss), and VPP access (aggregated batteries supply power to grids during peak hours for subsidies). Power utilities in Europe and America actively build VPPs with household batteries, helping families earn hundreds to thousands of euros annually. Diversified business models extend industrial value and push manufacturers to upgrade intelligent grid-connected control systems. Modern consumers prefer storage batteries with power saving, profit-making and power-resilience functions.