Powering your kayak’s electronics is a critical part of modern fishing and recreational paddling. From fish finders and GPS units to trolling motors and LED lighting, a reliable 12-volt battery is the unsung hero of a successful day on the water. Choosing the right one can mean the difference between locating your favorite honey hole and being left adrift with dead electronics.
With options ranging from lightweight lithium to traditional lead-acid, the best battery for your kayak depends on your specific power needs, budget, and how much weight you’re willing to carry. Our professional review breaks down the top contenders to help you find the perfect power source that offers longevity, safety, and the performance required for your aquatic adventures.
Our Top Picks for Kayak Batteries
- NERMAK 12V 10Ah Lithium LiFePO4 Deep Cycle Battery
- ECO-WORTHY Portable 12V 20Ah Lithium Iron Phosphate Battery
- Newport 12V50Ah Deep Cycle Heavy-Duty Marine Battery
- OKMO 12V 15Ah LiFePO4 Lithium Battery
- ML7-12 – 12 VOLT 7.2 AH SLA BATTERY – Mighty Max
- ML35-12 – 12 Volt 35 AH SLA Battery- Mighty Max
- Weize 12V 100Ah LiFePO4 Lithium Iron Phosphate Battery
- ExpertPower 12V 20Ah LiFePO4 Deep Cycle Battery
NERMAK 12V 10Ah Lithium LiFePO4 Deep Cycle Battery
The NERMAK 12V 10Ah battery is a compact and efficient lithium iron phosphate power source ideal for anglers with modest energy needs. Its high energy density and long cycle life of 2000+ charges make it a durable and reliable choice. The built-in Battery Management System (BMS) provides essential protection against overcharging, over-discharging, and short circuits, ensuring safety and longevity on the water.
This battery is well-suited for powering fish finders, small LED lighting, and other low-draw electronics on a kayak. Its very low self-discharge rate means it will hold a charge for long periods between trips. Weighing significantly less than traditional lead-acid batteries, it helps keep your kayak agile and easy to handle.
ECO-WORTHY Portable 12V 20Ah Lithium Iron Phosphate Battery
For kayakers who need more capacity without a significant weight penalty, the ECO-WORTHY 20Ah battery is a strong contender. Its compact dimensions and an ergonomic grip make it exceptionally portable and easy to stow in a kayak’s hatch or storage compartment. With an impressive lifespan of over 4000 cycles, this battery is built to last for many seasons of use.
This model offers versatile connectivity with both traditional terminals and a 5.52.5mm DC port, allowing you to power a wider range of devices directly. It’s an excellent power source for longer fishing trips where you might be running a fish finder, a small bilge pump, and a navigation light simultaneously. The built-in BMS ensures stable and safe operation in various conditions.
Newport 12V50Ah Deep Cycle Heavy-Duty Marine Battery
The Newport 12V50Ah is a sealed AGM (Absorbent Glass Mat) battery designed specifically for the demanding marine environment. If you are running a trolling motor from your kayak or have significant power requirements, this battery provides the robust, deep-cycle performance you need. Its sealed, leak-proof construction offers peace of mind, preventing acid spills no matter how choppy the water gets.
Weighing 32 pounds, it is considered lightweight for its capacity and power output compared to traditional flooded batteries. This makes it a practical choice for kayakers who require ample power and are willing to manage the extra weight for enhanced performance. Its compatibility with trolling motors and reliable power delivery make it a workhorse for serious anglers.
OKMO 12V 15Ah LiFePO4 Lithium Battery
The OKMO 12V 15Ah battery stands out with its advanced features and lightweight design, tipping the scales at just 3.5 pounds. It offers a remarkable cycle life and supports 100% depth of discharge, meaning you can use all of its stored energy without damaging the battery. This can provide a significant advantage during long days on the water.
Its built-in 15A BMS includes comprehensive protection and a special Low-Temperature Charging Protection feature, which adds an extra layer of safety for anglers who fish in cooler climates. For those with future expansion in mind, this battery can be connected in series or parallel, offering flexibility if your power needs grow.
ML7-12 – 12 VOLT 7.2 AH SLA BATTERY – Mighty Max
The Mighty Max ML7-12 is a small-form-factor, sealed lead-acid battery that provides a very budget-friendly option for basic power needs. Its maintenance-free design means there is no need to add water, making it a simple “set it and forget it” power source. This battery is perfectly sized for compact kayaks where space is at a premium.
It is an excellent choice for powering a single device like a basic fish finder or a small LED light bar for a few hours. While it lacks the cycle life and energy density of lithium options, its affordability and reliability make it a great entry-level battery for casual kayakers or as a dedicated backup power source.
ML35-12 – 12 Volt 35 AH SLA Battery- Mighty Max
The Mighty Max ML35-12 offers a substantial capacity increase over its smaller sibling, making it suitable for kayakers who need to run multiple electronics for extended periods. As a sealed AGM battery, it is safe for use in confined spaces and is resistant to vibration, a common occurrence on any watercraft.
This battery is explicitly noted for its compatibility with light trolling motors, such as those from Minn Kota, making it a versatile power center for a fishing kayak. It provides a solid middle ground between the high cost of lithium and the limited capacity of smaller lead-acid batteries, delivering reliable power for a full day of adventure.
Weize 12V 100Ah LiFePO4 Lithium Iron Phosphate Battery
For the kayak angler with the highest power demands, such as those using a powerful trolling motor over multiple days or running a full suite of electronics, the Weize 12V 100Ah battery is a top-tier solution. This lithium iron phosphate battery offers an immense capacity that can easily handle the most energy-intensive setups, all while maintaining a weight advantage over comparable lead-acid batteries.
The long cycle life inherent to LiFePO4 chemistry ensures this is a long-term investment. It is an ideal choice for larger kayaks or those configured for overnight expeditions where powering lights, communication devices, and a trolling motor is essential. This battery represents the pinnacle of capacity and performance for the serious marine enthusiast.
ExpertPower 12V 20Ah LiFePO4 Deep Cycle Battery
The ExpertPower 12V 20Ah battery is another excellent lithium option that balances capacity, weight, and performance. Known for its reliability, this deep cycle battery is built to provide consistent power for fish finders, small electronics, and lighting systems throughout your trip. Its lightweight construction helps maintain the nimble handling characteristics of your kayak.
Featuring a built-in BMS for safety, it protects against common issues that can shorten a battery’s life or create hazardous situations. This model is a trustworthy choice for anglers who value brand reputation and seek a dependable power source that won’t let them down after a few seasons of use.
Buying Guide: How to Choose the Best 8 Volt Battery for a Kayak
When I’m getting my kayak ready for a day on the water, the last thing I want to worry about is my battery dying. An 8V battery is the heart of many kayak fish finders and small trolling motors, so picking the right one is a big deal. It’s not just about grabbing the first one you see; you need to think about how you fish and what your gear really needs. Let’s talk about what I look for when I’m choosing a battery.
First and foremost, I always check the battery type. You’ll mainly find two kinds: sealed lead-acid (SLA) and lithium. SLA batteries are the traditional, more budget-friendly option. They get the job done, but they’re heavy. If you’re just doing short trips near the shore, an SLA might be fine. For me, lithium is the way to go. They are significantly lighter, which makes a huge difference when you’re carrying your kayak to and from the water. They also last longer on a single charge and can be discharged more deeply without harming the battery. The initial cost is higher, but the performance and lifespan are worth it for serious kayakers.
Next, I calculate the amp-hour (Ah) rating. This tells you how much energy the battery can store. A higher Ah rating means longer runtime. For a simple fish finder, a smaller battery like a 5Ah or 7Ah might be plenty for a full day. But if you’re running a more powerful fish finder with side imaging and a live scope, or if you’re using a small trolling motor, you’ll want something bigger, like a 12Ah or even 20Ah. I always plan for more capacity than I think I’ll need. It’s better to have power left over than to be paddling back in the dark because your electronics shut down.
The physical size and weight are critical for a kayak. Space is limited, and you’re already dealing with wind and current; you don’t want a bulky, heavy battery making things worse. I measure the storage compartment in my kayak and look for a battery that fits securely. A lightweight lithium battery is a game-changer for stability and ease of transport.
Finally, I consider the charging system. A smart charger that automatically switches to a float/maintenance mode once the battery is full is essential. It prevents overcharging, which can ruin your battery. Some batteries even come as a kit with a charger, which is super convenient. For the best 8 volt battery for a kayak, I prioritize a reliable, lightweight lithium option with enough amp-hours for my longest trips and a quality charger to keep it in top shape for seasons to come.
Frequently Asked Questions
How long will an 8V battery last powering my fish finder?
This is the most common question I get, and the answer depends on your battery’s amp-hour (Ah) rating and your fish finder’s power draw. You can find your fish finder’s amp draw in the manual or on the manufacturer’s website. Let’s say you have a 10Ah battery and your fish finder draws 1 amp per hour. In a perfect world, that would give you 10 hours of runtime. In reality, I always plan for about 80% of that to be safe, so around 8 hours. For a full day on the water, a 12Ah or higher battery is a safe bet.
Can I use a car battery in my kayak instead?
I strongly advise against using a standard car battery. They are not designed for the deep discharges that kayak electronics cause, and they are incredibly heavy and bulky. A heavy car battery will seriously affect your kayak’s stability and center of gravity, making it tippy and dangerous. They also contain liquid acid that can spill. Stick with a purpose-built marine deep-cycle battery, either SLA or, my preference, lithium.
What is the main difference between lead-acid and lithium batteries for kayaks?
The main differences are weight, lifespan, and performance. Lead-acid batteries are heavier, have a shorter overall lifespan (fewer charge cycles), and shouldn’t be discharged below 50% regularly if you want them to last. Lithium batteries are much lighter, can be discharged to almost zero without damage, last for many more charge cycles, and hold their voltage consistently, which often means better performance from your fish finder. For most kayak anglers, lithium is the superior choice.
How should I store my kayak battery during the off-season?
Proper storage is key to making your battery last. I always make sure to give it a full charge before storing it. For a lead-acid battery, you need to put it on a maintenance charger or give it a top-up charge every few months to prevent it from dying. Lithium batteries are easier; just charge it to about 50-60% and store it in a cool, dry place. They have a very low self-discharge rate, so they’ll be ready to go when you are.
Do I need a special charger for an 8V lithium battery?
Yes, absolutely. You must use a charger designed for the specific chemistry of your battery. Using a lead-acid charger on a lithium battery can be dangerous and will definitely damage it. A proper lithium charger will have the correct charging algorithm and safety features. Many of the best 8 volt battery for a kayak options sold as kits include the correct charger, which is a great way to ensure compatibility.
Is it safe to leave my battery in the kayak while it’s stored?
I never recommend leaving any battery in your kayak for long-term storage. Temperature extremes, both hot and cold, can degrade the battery and shorten its life. Moisture is also a constant enemy. It’s a simple habit to remove the battery after each trip, store it indoors, and keep your gear in the best condition possible.