This style of hedgetrimmer has become increasingly popular over the last few years due to the major developments in battery technology.
Battery Powered Cordless Hedgetrimmers are now powered by Lithium-Ion or NiCad batteries, which run for longer, take far less time to charge than conventional rechargeable batteries (usually around an hour) and, amazingly, do not leak power so you can put them away and re-use them weeks later without loss of power. The Lithium Ion type are the more contemporary and probably more efficient.
These modern batteries are also much lighter (very roughly half the weight of conventional rechargeable batteries) and far more compact, making battery powered cordless hedge trimmers even lower in weight generally than their mains operated cousins.
All Battery Powered Cordless Hedgetrimmers have double-sided blades and are suitable for smaller gardens. They are convenient and ‘go-anywhere’ as they can be used wherever you want. They are also relatively low noise, like mains powered hedge trimmers.