While we are waiting for iFixit to tear apart the new iPad so we can get a look at the device’s new 42.5-watt-hour rechargeable lithium-polymer battery, we received confirmation that the battery does take hours longer to charge than the iPad 2 (iPad 2 pictured above). We know battery life remains the same with the 70 percent larger battery going mostly toward powering the new Retina display, A5x chip, and LTE-capabilities, but we wondered last week whether the new battery could take up to 70 percent longer to charge. MG Siegler confirmed in his review on TechCrunch that charging the new iPad takes “several hours” longer compared to earlier generations:

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So how was Apple able to keep the battery life the same while adding LTE and without drastically changing the design? It appears that they’ve had a fairly major breakthrough in their battery technology. While the new battery clearly isn’t much bigger than the old one, it can hold much more juice (42 watt-hours versus 25-watt-hours). The downside of this is that I’ve found it takes quite a bit longer to charge the new iPad. As in several hours — you’ll probably want to do it overnight.

While it is unclear exactly what is causing it, Siegler also noted in his review a noticeable warmth coming from the bottom left corner of the new iPad: “It’s never hot, just warm.” The larger battery will presumably cover most of the surface area of the device, which makes LTE the likely cause. The Verge confirmed in its review that the new iPad gets “a bit warm” when using LTE for extended lengths of time, which we know is often an issue with LTE devices. Siegler speculates the battery or LTE is the cause of the heat, but we will have to wait for a full tear down before we know for sure. iFixit is tearing down the device as we speak, so we will update with official details on the battery soon.