Renata Watch and Battery Analyzer (RENATA-BWT94) - $44.95
Victron Energy Blue Smart IP65 12-Volt 5 amp Battery Charger (Bluetooth) | eBay
Digital Battery Tester Checker 1.5V And AA AAA Cell BT-168D LCD Power Measure | eBay
Amazon.com: LCD Battery Capacity Monitor Gauge Meter,Waterproof 12V/24V/36V/48V Lead Acid Battery Status Indicator,Lithium Battery Capacity Tester Voltage Meter Monitor Blue Backlight for Vehicle Battery : Automotive
SKYRC NC 1500 Charger for cylindrical cells AA , AAA | Conrad.com