Ridgid just updated its 18-volt X4 Hyper Lithium batteries with new internal technology designed to improve performance and extend overall lifetime. Available in both 2.0- and 4.0-Ah sizes, the batteries can operate in extreme temperatures, from 29 F (-20 C) to 158 F (70 C). In addition, they now have short-circuit, over-discharge, and over-current protection. The company also released a new charger that it claims fills these batteries 50% faster than earlier models. Price: $80 for 2.0 Ah and $120 for 4.0 Ah. COO: China. 800.474.3443. ridgid.com.