A pair of adhesive strips refuse to let the battery go. Fortunately, we at iFixit are masters of removal.

The 3.7 V, 4000 mAh battery provides an advertised 11.5 hours of reading time, which easily beats the Kindle Fire's 8 hours.

Even though the battery says the model is "NOOKCOLOR," the Nook Tablet's battery life is 3.5 hours longer than that of the Nook Color.