Do you know what type of guns they had early in the war? Sikakis indicates that the battery was equiped in the first quarter of 1864 with five 6 pdr bronze smoothbores and one 3.3" rifle. In May 1864, armed with two 6 pdr smoothbores, one 3.3" rifle and one 12 pdr howitzer.
Sikakis also says that the recrossed the Mississsippi River in 1865 and were surrendered in the Trans-Mississippi. This seems a very unlikely tale. I am not aware of many formal moves back accross the river after Slemons came back from Price's Raid in 1864.