Is it just me or would the AA batteries not deliver less power than the ones that came in the laptop already or has he not explained it right?
<Picture of rechargeable AA 1.2v 2700mAh batteries>Since this entire pack is rated at 9.6V @ 3000mAh this tells me there are two individual packs rated at 4.8V @ 3000mAh each. Each boxy cell is probably rated at 1.2V @ 3000mAh each. This battery pack is from an older notebook.
A single one of these AA NiMH cells is also rated at 1.2V, yet can deliver nearly 3.6 times more energy at a far smaller size than your boxy Toshiba cells from even a few years ago. If I was so inclined to replace the cells inside the pack with these eBay AA batteries, in theory, this would yield me a battery pack rated at 9.6V at 10,800mAh or roughly 3.6 times more running time and still be essentially compatible, and more interestingly, they will fit pretty easily inside with space to spare. But, that's a mod for another time.