Group 31 Deep Cycle Marine Battery, 105 Amp Hours, 650 Cold Cranking Amps, 800 Marine Cranking Amps, 185 Reserve Minutes

A great battery for your house bank or trolling motor

Powering a trolling motor or house bank demands a battery built to go the distance, and the West Marine Group 31 Deep Cycle Battery delivers exactly that. Engineered with lead-calcium technology, this 105Ah battery delivers more power per pound than conventional dual-purpose batteries, so you get reliable, sustained performance across long days on the water. With 650 Cold Cranking Amps and 185 reserve minutes, it also pulls double duty as an emergency starting battery when your engine's CCA requirements align. Manufactured in the USA by East Penn, one of the most trusted battery manufacturers in the country, each unit passes more than 250 quality-control checks before it ever reaches your boat.

Durability and safety are built into every detail. The no-spill design allows safe operation at heel angles up to 45 degrees, making it a smart choice for sailboats and powerboats alike. Molded-in stainless steel SAE posts paired with vertical 5/16" stainless steel studs and hex nut terminals resist corrosion and simplify installation, eliminating the loose hardware and connection failures that plague standard terminals. Low-resistance separators improve current flow for faster, more reliable starts, while superior electrolyte retention protects against dry-out and acid leaks even under extended cycling demands.

Beyond performance, this battery reflects a commitment to responsible manufacturing. East Penn's award-winning facility operates on closed-loop, sustainable practices, recycling nearly all plastics, lead, and acid used in production. When you choose this battery, you're investing in dependable power for your boat and making a choice that's better for the environment.

Key Features

• Deep cycle design handles sustained power draws that standard batteries cannot
• Ideal for trolling motors, house banks, and auxiliary power systems
• Can serve as an emergency start battery when the CCA specification matches the engine requirements
• Lead-calcium construction delivers more power per pound than competitive dual-purpose batteries
• No-spill design allows safe operation at up to 45 degrees of heel
• Molded-in stainless steel studs and hex nut terminals resist corrosion and simplify connections
• Low-resistance separators improve current flow for faster, more reliable starts
• Superior electrolyte retention prevents dry-out and acid leaks
• Manufactured in the USA by East Penn with 250+ quality control checks per battery
• East Penn factory uses closed-loop recycling for lead, acid, and plastics

Specifications

• Group Size: Group 31
• Terminal Type: Molded-in SAE posts and vertical 5/16” NEG., 5/16” POS stainless steel studs with hex nuts
• Amp Hours (Ah): 105
• Cold Cranking Amps (CCA): 650
• Marine Cranking Amps (MCA): 800
• Reserve Minutes: 185
• Weight: 60
• Dimensions: 13"L x 6 3/4"W x 9 1/2"H
• Warranty: 12-month free replacement

A core charge will apply to battery purchase if an old 12V battery is not exchanged at the time of purchase.