Battery Model: D31M Part Number: 8052-161 Nominal Voltage: 12 volts NSN: 6140 01 502 4405 Description: High power, dual purpose engine start and deep cycle, sealed lead acid battery Physical Characteristics: Plate Design: Electrolyte: Case: Color: Group Size: Length: Width: Height: Weight: High purity lead-tin alloy. Wound cell configuration utilizing proprietary SPIRALCELL® technology. Sulfuric acid, H2SO4 Polypropylene Case: Light Gray Cover: “OPTIMA“ Blue BCI: 31 Standard 12.813” 6.500” 9.375” 59.8 lb Metric 325.4 mm 165.1 mm 238.1 mm (height at the top of the terminals) 27.2 kg Terminal Configuration: SAE / BCI automotive and threaded stainless steel stud 5/16 – 18 UNC. Performance Data: Open Circuit Voltage (fully charged): Internal Resistance (fully charged): Capacity: Reserve Capacity: 13.1 volts 0.0025 ohms 75 Ah (C/20) BCI: 155 minutes (25 amp discharge, 80°F (26.7°C), to 10.5 volts cut-off) Power: CCA (BCI 0°F): 900 amps MCA (BCI 32°F): 1125 amps Recommended Charging: The following charging methods are recommended to ensure a long battery life: (Always use a voltage regulated charger with voltage limits set as described below.) Model: D31M These batteries are designed for starting and deep cycling applications and for use in boats with large accessory loads.

Recommended Charging Information: Alternator: 13.65 to 15.0 volts Battery Charger (Constant Voltage): 13.8 to 15.0 volts; 10 amps maximum; 6-12 hours approximate Float Charge: 13.2 to 13.8 volts; 1 amp maximum (indefinite time at lower voltages) Maximum voltage 15.6 volts. No current limit as long as battery temperature remains below 125°F (51.7°C). Charge until current drops below 1 amp. Rapid Recharge: (Constant voltage charger) Cyclic or Series String Applications: 14.7 volts. No current limit as long as battery temperature remains below 125°F (51.7°C). When current falls below 1 amp, finish...