The battery also offers a socket which allows people to charge their mobile phones, something that was far from easy before.

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When completely empty it takes a maximum of eight hours to fully charge the battery at a household socket or charging station on the electricity systems of most countries i.e. overnight.

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Using a dedicated high-current electric circuit, like those installed for electric ovens, these can recharge the MINI E in 4.5 hours. (With an ordinary mains socket, by contrast, recharging could take all day.) For cars with smaller battery packs, like the Smart, overnight recharging from a conventional socket is possible.

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These devices transform the direct current generated by a solar panel or electric car battery into the alternating current you expect from a wall socket.

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On the bottom, there's a standard tripod socket, an SD card slot and a battery compartment, complete with an 875mAh LP-E12 cell (replacements should run you about 75 bucks).

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The first socket is used to charge the lithium-ion battery and the second can be used to connect electrical devices such as coolers or camping lights.

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Instead, you socket one of two hot-swappable lithium-ion battery cartridges into the back of the mouse, and put the second in a charging station that doubles as the 2.4GHz wireless transmitter and holds additional weights for the Rat as well.

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Instead, it makes use of a rechargeable battery, which you can top off using the on-board micro-USB socket.

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We're pressing on with battery research for plug-in hybrid vehicles that can be powered by electricity from a wall socket, instead of gasoline.

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