Black & Decker BCS10B 10 Amp 12V Simple Battery Charger With Digital Scrolling LCD Display $32.99 with Free Shipping ($69.99 Retail). This 12 Volt Battery Charger contains an LCD screen that displays the battery voltage, charge rate and battery diagnostics. It provides alternator diagnostics, cord or cable wrap and clamp storage that allows the unit to store safely as well as compactly. This charger consists of high frequency charge process that charges 12V batteries quickly and a reverse polarity alarm which warns against improper connections to battery.