I'm not familiar with a Lock's Battery from SC, but there was a 1st SC Militia Artillery Regiment, commanded by COL E. H. Locke. This regiment entered state service on 27 December 1860, when troops under the command of LTC Wilmot Gibbes DeSaussure, were sent to occupy Fort Moultrie on Sullivan’s Island. Four batteries were stationed on Morris Island during the bombardment of Fort Sumter in April 1861. Most of the batteries were subsequently transferred to Confederate service as independent commands between August and November 1861. Companies A-C were called to active duty at Charleston in July 1863, under COL John A. Wagener, and were disbanded on 26 September 1863, so that their members between the ages 40 and 50 could be recruited for the 3d SC Infantry, State Troops. Remnants of the regiment are reported to have served with Taliaferro’s Division in early 1865.

So far as I know, no rosters of the regiment exist, but there are some for the batteries that subsequently entered Confederate service. However, none of these were commanded by an officer named Lock/Locke.

Hope this helps.