I don't feel like you would be able to. The only difference on the batteries is the move from a 7.2V battery to a 7.4V high voltage chemistry. The firmware in the laptop is configured to charge the batteries to the pre-defined voltage in the firmware. Chances are, if the laptop did not outright reject the battery pack (especially if the part ID is read off the battery pack itself), it would not charge the pack above 7.2V, giving you a 52Whr battery pack anyways. I would just stick to what the laptop came with.