The Canon LP-E4N Battery is the power source for the Canon EOS 1D Mark X DSLR.
The Canon LP-E4N Battery Pack is both forward and backward compatible with the Canon LP-E4 Battery Pack found in the recent-prior 1-Series bodies.
It is also compatible with the Canon EOS 1D Mark IV DSLR, Canon EOS 1D Mark III DSLR and Canon EOS 1Ds Mark III DSLR. I always have one or more spare batteries on hand. With the number of frames a single LP-E4N charge delivers, I often leave the charger at home even when traveling.
Utilizing a larger number of smaller cells, the LP-E4N capacity increased from 2300mAh to 2450mAh. A new battery charger, the Canon LC-E4N, is required to fully charge the new batteries. The LC-E4 charger will charge LC-E4N batteries to only about 90% capacity.