DC batteries connect directly to solar panels before the inverter, offering higher efficiency but requiring compatible inverters. AC batteries connect after the inverter and work with any solar system but have slightly lower efficiency due to multiple energy conversions.

Home battery systems range from $10,000-$20,000 installed, depending on capacity and features. Popular options like Tesla Powerwall (~$15,000 installed) offer 13.5 kWh capacity. Federal tax credits apply to batteries when installed with solar systems.

Yes, batteries can often be retrofitted to existing solar systems, though the process varies by system type. String inverter systems may require additional equipment, while systems with power optimizers or microinverters typically integrate more easily with battery storage.

Most lithium-ion solar batteries last 10-15 years or 6,000-10,000 charge cycles. They typically retain 70-80% capacity after their warranty period ends. Proper installation, temperature control, and usage patterns can extend battery life.

Battery runtime depends on your energy usage and battery capacity. A typical home battery (10-13 kWh) can power essential loads (lights, refrigerator, internet) for 8-24 hours, or run a whole home for 4-8 hours during normal usage patterns.

Solar batteries store excess energy generated during the day for use at night or during power outages. They provide energy independence, backup power during blackouts, and can help you maximize your solar investment by reducing reliance on grid electricity during peak-rate periods.