There are few surprises left about Google's upcoming Nexus 5X and 6P, which are expected to be announced on Tuesday at an event in San Francisco. But a cache of leaked slides on the Huawei-made Nexus 6P do tell us a few more interesting details about this phablet.

Read next: The Nexus 6P review.

Most notably, it looks like Google is focusing on battery life this time around. The Nexus 6P should last a pretty long time in your pocket thanks to a giant 3,450mAh battery. That cell is larger than the batteries found in other newer phablets like the Galaxy Note 5 (3,000mAh) and iPhone 6S Plus (2,750mAh), and it represents a 14 percent improvement over the Motorola-made Nexus 6 (3,220mAh) it is replacing.

It's not just a massive battery that will keep the Nexus 6P from dying on you — thanks to the new Doze feature and other power-saving improvements in Android M. Doze promises to vastly improve battery life while in standby by smartly reducing background app refreshing. It's said to as much as double battery life on standby.

Other than the big battery, the slides confirm many details we've already heard, such as a rear-mounted fingerprint reader, a 2560 x 1440 display, a Snapdragon 810 processor, and USB-C. But the slides do give us a couple more details on the phone's design: it will feature a "metal unibody" design and it will have a Gorilla Glass 4 screen. As earlier reported, it will come in four colors — black, white, silver, and gold — though gold will apparently only be available in Japan at launch.