High Cranking, Low Weight

Starting Lithium Batteries

Lithium cranking power that turns the engine over hard and weighs a fraction of the lead-acid battery it replaces.

Lithium vs. Lead-Acid
All Lithium Deep Cycle Dual Purpose Starting
Also Shop Cranking/Starting AGM Starting Lithium-Compatible Chargers

Starting LiFePO4

Cranking-rated lithium in standard group sizes.

Shop all cranking batteries
Turn It Over, Every Time

Lighter on the Bow, Harder on the Starter

Weight on a boat or a machine is never free — every pound in the battery tray is a pound you carry all day. Lithium cranking batteries deliver the burst a starter needs at a fraction of the mass, which is why they show up first on the boats where trim matters most.

Lightweight & Long-Lasting
A fraction of the weight of lead-acid
36-Mo Free Replacement
Plus a 10-year limited warranty
45 Years of Expertise
Dependable battery solutions since day one
Trusted by Professionals
Anglers, courses, fleets and dealers alike

Cranking Power Without the Weight

Talk to a battery expert

Where Starting Lithium Fits

Outboards, inboards and utility engines.

Lithium vs. Lead-Acid

Why Pro-Guide customers make the switch.

Specification Lead-Acid (standard) Pro-Guide LiFePO4
Weight ~65–70 lbs per battery ~24–28 lbs per battery
Lifespan 1–2 years typical 10+ years
Charge time 8+ hours 2–3 hours
Maintenance Regular watering and terminal checks None
Warranty 90 days – 1 year 10-year limited + 36-month free replacement

Compare Starting Batteries

Because our customers shop by the numbers.

ModelVoltageCapacityGroup SizeBest ForPrice
12V 390CCA Group U1 LiFePO4 Starting Battery 12 3AH U1 Light, high-crank starting power $119.99
12V 100AH Group 24 LiFePO4 Starting Battery 12 100AH 24 Group 24 cranking with usable capacity $899.99
12V 1150MCA Group 31 AGM Starting Battery 12 — 31 Highest marine cranking amps we stock $423.95

Frequently Asked Questions

Choosing the Right Battery

How many cranking amps do I need?

Match or exceed the cranking rating your engine manufacturer specifies — going higher does no harm. Each product page lists the cranking figure so you can compare directly against the battery you are replacing.

What does LiFePO4 mean, and why does Pro-Guide use it?

LiFePO4 — lithium iron phosphate — is the most thermally stable lithium chemistry in common use. Compared with lead-acid it holds voltage under load far longer, weighs a fraction as much for the same usable capacity, and needs no watering or terminal maintenance.

How do I know which group size I need?

Group size describes the case dimensions and terminal layout, not the capacity. Match the group size stamped on your current battery — every product page lists the group size and dimensions so you can confirm it fits the tray you already have.

Charging & Maintenance

Can I keep using my existing lead-acid charger?

A lead-acid charger can undercharge a lithium pack and shorten its life. Use a lithium-compatible charger — everything in our Lithium-Compatible collection is profiled for LiFePO4.

What maintenance do these batteries need?

None of the routine watering or terminal cleaning that flooded lead-acid requires. The built-in BMS manages charge and discharge protection automatically.

Warranty & Support

What warranty comes with these batteries?

Terms vary by product line — the term for each battery is listed on its product page, and the full details are on our Warranty Information page. Register your battery online after purchase to activate coverage.

What if I am still not sure which one to buy?

Call our US-based battery team on 1-800-827-3232 before you order. Tell us the machine, the tray you are working with and how long you need to run between charges, and we will point you at the right part number, or message us.

Cranking Power, Half the Weight

Match a lithium starting battery to your engine and your tray.

Shop Starting LithiumTalk to an Expert