The Shure SB930 Rechargeable Battery powers the MXCW640 Wireless Conference Unit for over 11 hours. LED indicators on the battery display charge status quickly and easily. Charging in the MXCWNCS Networked Charging Station takes just 1.5 hours for a 50% charge, and 4 hours for a 100% charge. The SB930 Rechargeable Battery powers the MXCW640 Wireless Conference Unit for over 11 hours. LED indicators on the battery display charge status quickly and easily. Charging in the MXCWNCS Networked Charging Station takes just 1.5 hours for a 50% charge, and 4 hours for a 100% charge.