Global batteries.co.uk are your best buy for these external batteries - they have a tech. e-mail support so you can contact them and ask whatever you like.. Id did - replied real quick. Also looked up which was best for my laptop too. I have ordered one. Have already bought the normal internal battery for my laptop from them (which needed replacing). Good luck
Just to say, you can run a laptop off of a "car" battery, that's 12 Volts DC, through an adaptor that plugs into a "lighter" socket, and gives out 15 to 24 Volts DC (my Laptop runs on 19 Volts DC). You should check that the adaptor comes with a plug the same as your Laptops 240 (Mains) adaptor, to plug into the Laptop. (The Voltage your laptop requires should be printed on the mains adaptor "brick".
Just a thought! :)
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