All the information I've seen says they use stock Panasonic NCR-18650A lithium ion batteries just like clumsysmurf said. (The "A" just means that it's the 3100mAH nominal capacity version - there are several NCR-18650 batteries with different capacities.)
It's a fairly common 18650 battery, lots of laptops use this specific model.
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All the information I've seen says they use stock Panasonic NCR-18650A lithium ion batteries just like clumsysmurf said. (The "A" just means that it's the 3100mAH nominal capacity version - there are several NCR-18650 batteries with different capacities.)
It's a fairly common 18650 battery, lots of laptops use this specific model.