Whether it’s already time to replace your boat’s batteries or you’re dreading eventually having to, you may be considering making the switch to lithium batteries. With many advantages over lead-acid batteries, lithium batteries are becoming extremely popular in the marine world.

However, these batteries do come with an increased upfront cost. So, how much more do lithium batteries cost than lead-acids, and are they worth the extra money?

Lead-Acid Batteries

Lead-acid batteries are the most commonly used battery type for boats. This may be slowly changing, but they’re likely what you already have installed in yours right now. Lead-acid batteries are the cheapest option when shopping around for marine batteries.

The overall pricing for lead-acid batteries can vary greatly. Whether you’re powering a bass fishing boat, a houseboat, or a yacht, the amount and type of batteries you’ll need are different.

Starting batteries that crank the engine have a different cost than deep-cycle batteries that power your house electronics or trolling motor. Dual-purpose batteries that can do both will have a different price tag. You can also choose between a flooded lead-acid battery or a sealed AGM battery.

Also, high-quality brands will be more expensive than less well-known brands. However, not only will they last longer because of the quality, but they’ll also likely be under warranty. All these factors will play into how much your battery bank costs. For that reason, we’ll just compare the cost of one lead-acid battery to one lithium battery.

The price of one 215Ah 12V flooded lead-acid battery is around $350. A sealed AGM battery that’s 212Ah 12V is about $650. Since lead-acid batteries can only be depleted down to 50% to prevent damage, only half the Ah in these batteries is actually usable, so about 100Ah for each.

Lithium Batteries

Lithium batteries provide many benefits compared to lead-acid batteries. They’re lighter, maintenance-free, provide consistent power, and last longer. However, they’re quite a bit more expensive upfront.

Pricing for these batteries can also vary. Although these batteries don’t come in as many different types, the voltage, Ah, and brand can change the cost. Just like lead-acid batteries, well-known brands will charge more for their product. Again, you’ll likely get a warranty and a better quality brand for that extra cost.

One 100Ah 12V lithium battery will cost around $800. That’s roughly $450 more than a flooded lead-acid and $150 more than a sealed AGM. This may seem like a huge difference, especially as one lump sum, but over time, you’ll actually save money by switching to lithium.

Cost Savings Over Time

While you’ll have to shell out more money upfront if you choose lithium batteries, you’ll actually be getting the better deal in the long run.

For one, lithium batteries last three to five times longer than lead-acid batteries. Lead-acid batteries get 500 to 1,000 charge/discharge cycles while lithium batteries get 2,000 to 5,000 cycles. This means you won’t have to buy replacements even half as often as you would if you went with lead-acid again.

On top of that, lithium batteries can be fully discharged, while lead-acids can’t be depleted past 50%, so you’ll get double the usage out of each charge.

You’ll also save money on fuel because lithium batteries are about a third of the weight of lead-acid batteries. You’ll get better fuel efficiency, along with better speed and performance. You can even save some money by installing them yourself instead of hiring someone else since they’re easier to pick up and maneuver into place.

If you take your boat in for maintenance, you can save some money there, too. Unlike lead-acid batteries, lithium batteries don’t contain acid. This means they don’t require any of the maintenance that lead-acids do, such as checking acid levels, adding water, cleaning corrosion, etc.

Lithium Advantages

While there’s no rush to convert your boat over to lithium batteries, the benefits and advantages you’ll receive may well be worth it.

Besides the perks we’ve already mentioned, lithium batteries offer consistent power, no matter the charge level. Lead-acids lose voltage and power as they’re depleted and under heavier loads, which means you’ll gradually lose speed and performance while you’re out on the water. Lithium batteries don’t have this problem, so you’ll get the same voltage at all times.

Plus, lithium batteries are a safer option. Since they don’t contain acid, you don’t have to worry about leaks, which could damage your boat or the environment. They also have a built-in BMS, which monitors the battery and protects it from overheating, overcharging, and other types of damage.

Here’s a quick recap on the perks of switching to lithium batteries for your boat:

• Lighter weight
• Faster speeds
• Energy efficiency
• Longer battery life
• Zero maintenance
• Better performance
• Cost-savings over time
• Increased safety and reliability

If you’re debating whether or not to make the switch from lead-acid to lithium batteries, consider how important each of these advantages is to you. If you can afford the initial investment, lithium batteries will be well worth the added upfront cost.