A Extension Cable can be used to extend a Portable Charger (3 pin of Type F/Shucko standard domestic socket charging cable).
Please note that the Extension Cable will only allow charging at the rate permitted by the Portable Charger, and that the IP rating will be IP54 rather than the IP66 most commonly found with Portable Chargers.
Single Phase Type 1 Extensions can be found here
Single Phase Type 2 Extensions can be found here
This solution would be perfectly fine for most domestic situations, however our ideal recomendation would be that a longer Portable Charger be purchased to ensure the best IP rating.