Will a 77++ battery fit a Lenovo P50

[baertracks]

Will a 77++ battery fit a Lenovo P50?
I'm seeing contradictory information on the Internet.
Some eBay sellers say that a 77++ will work with the P50, P51 and P52.
Other sources say that the 77++ is designed to only fit the P52.
Can anyone clarify for me?
I need to replace my P50 battery (which is using a 77+) and want to know if getting a 77++ might be an option to consider.
Thanks
FRANK