Electrochemical energy storage products, also known as "Battery Energy Storage System" (or "BESS" for short), at their heart are rechargeable batteries, typically based on lithium-ion or lead-acid controlled by computer with intelligent software to handle charging and dischargning cycles. Companies are also developing smaller flow battery technology for home use. As a local energy storage technologies for home use, they are smaller relatives of battery-based grid energy storage and support the concept of distributed generation.