How to choose battery for kayak fish finder?

So wählen Sie die Batterie für den Kajak-Fischfinder aus?

Kayaking and fishing are activities that combine tranquility with the thrill of the catch. A kayak fish finder can be crucial in finding the best fishing spots. However, a fish finder is only as good as the battery that powers it.

When choosing the right kayak fish finder battery, there are many factors to consider to ensure uninterrupted performance and durability. In this comprehensive guide, we'll go over the nitty-gritty to help you choose the best battery for your fish finding needs.

Understanding Kayak Fish Finder Power Requirements

The first step in choosing a battery is to know the power requirements of your fish finder. These electronic devices are usually powered by a 12V system, but the power consumption may vary. A small, simple fish finder may require as little as 0.1A of current, while more advanced models with GPS and color displays may use 1A or more. You can find this information in your device manual. They are essential for choosing a battery with the right capacity.

Battery types and technology

After determining your power needs, explore battery types to find which best suits your setup.

Lead-acid batteries

Traditional lead-acid batteries are widely used due to their affordability and availability. In this category, sealed lead-acid (SLA) batteries, including Absorbent Glass Mat (AGM) batteries, are preferred by kayakers because they are maintenance-free and leak-proof.

AGM batteries represent a step forward and are known for their better charge retention and longer lifespan compared to traditional SLA batteries.

Lithium-ion batteries

Lithium-ion alternatives are the newer technology on the market. These batteries feature higher energy density, meaning they can hold more power despite their size and weight.

They provide a constant level of voltage throughout the discharge cycle and typically have a much longer lifespan than lead-acid batteries.

Battery capacity and runtime

The capacity of a fish finder battery is crucial because it determines how long you can use your device on the water. You need to assess the following:

Rated Capacity (Ah):Batteries are rated in Ampere Hours (Ah). This value gives an indication of how many amps a battery can deliver in one hour. A battery capacity of 7-20 Ah is usually sufficient for kayak fishing, but you should calculate your specific needs based on the power consumption of your fish finder and your expected usage time.

Estimating Runtime: A simple formula for estimating battery life is to divide the Ah rating of the battery by the current draw of the fish finder. For example, a 10Ah battery powering a device at 1A could theoretically run for 10 hours.

Kayak size and weight restrictions

Because kayaks have limited space and buoyancy, the size and weight of your battery are important. Lithium-ion batteries are often preferred because they are significantly lighter and more compact. If space is at a premium, heavier lead-acid batteries may not be practical.

Durability and environmental resistance

Kayaking environments require a high level of equipment. Batteries are exposed to moisture, temperature fluctuations and shocks. Waterproof batteries with robust construction are preferred. While some batteries are sealed waterproof, the use of additional protective battery cases provides an additional layer of protection against damage from water and shock.

Loading and lifecycle considerations

When it comes to charging, not all batteries are the same:

  • Lead-acid batteries typically require longer charging time and may require maintenance with trickle chargers when not in use.
  • Lithium-ion batteries charge faster and require no maintenance between uses.
  • Life cycle: Evaluate how many charge cycles the battery can withstand before its capacity decreases. Lithium batteries often allow thousands of cycles, compared to the few hundred cycles typical of lead-acid models. Lithium batteries from Timeusb have a lifespan of more than 4000 years, which corresponds to a lifespan of over 10 years.

Compatibility and assembly

Before purchasing, make sure the dimensions of the battery fit into the battery space provided for your kayak. Also consider cables, chargers, and additional equipment the battery may need. Many batteries are sold with mounting kits or have proprietary systems to secure them into kayaks; Compatibility with your existing setup is key.

Safety first

Security cannot be overemphasized. Batteries pose inherent risks such as fire or chemical hazards, especially if damaged or used improperly. Choose batteries with built-in safety features like circuit protection and thermal shutdowns. Always follow the manufacturer's charging and storage guidelines.

Budget and long-term costs

Assess not only the upfront cost, but also the value over the life of the battery. While lead-acid batteries may be cheaper initially, you may end up having to replace them more often than a lithium-ion battery, which may have a higher initial cost but could provide greater value in the long run due to its durability and longer lifespan.

Why lithium batteries are a better choice for fish finders

Below is a table showing why a lithium battery is a better choice.


Advantages of lithium batteries

Disadvantages of lead-acid batteries


Significantly lighter, which makes transport easier and puts less strain on the kayak.

Heavier, which can be cumbersome in a kayak and can affect buoyancy and maneuverability.


The compact size offers more flexibility when placed on a kayak.

Generally larger and bulkier, requiring more space, which is at a premium in a kayak.


Higher energy density, meaning they can store more energy and allow fish finders to last longer.

Lower energy density requires larger batteries for the same capacity, which leads to weight and space problems.

Charging efficiency

Fast charging capability and more efficient power delivery, meaning less downtime and more time on the water.

Longer loading times and less efficient power consumption, which can lead to longer waiting times between applications.


Longer lifespan with thousands of charge cycles, reducing the need for regular battery replacement.

Fewer charging cycles can lead to more frequent replacements over time.


Virtually maintenance-free, with no need for constant monitoring or trickle charging to maintain battery health.

To ensure a long lifespan, regular maintenance is required, which can be inconvenient for kayak anglers.

Voltage stability

Maintain constant voltage levels throughout the discharge cycle, ensuring the fish finders operate optimally until the battery runs low.

When the battery is discharged, significant voltage drops can occur, which can affect the performance of the fish finder.

Environmental impact

They generally have a lower impact on the environment due to their longer lifespan and the absence of hazardous substances such as lead and acid.

Contains lead, acid and other chemicals that have the potential to be harmful if disposed of improperly.

Acquisition costs

More expensive initially but becomes more cost effective over time due to durability and longevity.

The upfront cost is cheaper, but may be more expensive in the long run due to replacement and maintenance costs.

Safety devices

Often equipped with advanced safety features to protect against overcharging, overheating and short circuits.

Advanced safety features may be missing, which may increase the risk of accidents, especially in demanding kayaking environments.

Temperature resistance

Better performance in a wide temperature range.

Performance may deteriorate in extreme temperatures, which can be typical in some kayaking situations.

Discharge rate

Lower self-discharge rate, allowing charge to be retained longer when not in use.

A higher self-discharge rate requires more frequent charging, even when the battery is not in use, to maintain the health of the battery.

Best fish finder battery for your boat or kayak

Selecting the perfect battery for your fish finder is crucial for smooth operation on the water. The essential features to consider include the compactness of the battery, its resistance to water ingress, its robustness and its portability.

It is important to accurately measure the battery's ampere-hour rating (Ah). This ensures compatibility with your fish finder's power needs and guarantees a stable and sufficient power reserve to maintain operation throughout your fishing trip.

For a robust and reliable marine grade power source, we recommend using the Timeusb 12V 50Ah or 100Ah fish finder batteries. These units offer a harmonious blend of efficiency, capacity and reliability and are specifically tailored to the marine environment of boats and kayaks.

Fishfinder Battery FAQs

1. How long can a fish finder run on a 12 volt battery?

When using a fish finder with a typical power consumption of around 2A, you can expect a fully charged 12V 100Ah (amp hour) battery to power the device for around 50 hours. In contrast, power requirements for trolling motors are higher, often using 1A per pound of thrust at full power. For example, if you run a 50 pound thrust engine at maximum capacity, the battery can be completely discharged within two hours. To ensure a long battery life, it is important to avoid deep discharges - it is recommended to keep the battery at over 50% to 80% of its full capacity - and to recharge it soon after use.

2. Does a fish finder need its own battery?

A separate, dedicated battery for a fish finder is not mandatory. Often, a fish finder can efficiently share a boat's main battery with other electronic devices such as navigation devices, radios or lighting systems.

However, using an exclusive battery for your fish finder can bring certain advantages. On the one hand, it guarantees a stable and uninterrupted power supply, which is crucial when other on-board electronics draw a lot of power from the main battery. Additionally, a dedicated battery optimizes power management and electrical design, potentially simplifying installation and maintenance procedures.

3. Can you operate a fish finder with a deep cycle battery?

You can actually power a fish finder with a deep cycle battery. These batteries are designed to provide reliable, long-lasting power delivery, facilitating the continuous operation of devices such as fish finders, trolling motors and additional marine electronics. Due to their durability and ability to discharge continuously, deep cycle batteries are suitable for the needs of fish finders and similar applications.


The ideal kayak fish finder battery strikes a balance between capacity, size, weight, durability, rechargeability, compatibility, safety and cost. By thoroughly evaluating each factor based on your specific needs, you can improve your fishing trips with uninterrupted access to your fish finder's insights.

Whether you choose the economics and availability of lead-acid batteries or the efficiency and performance of lithium-ion options, making the right choice means you can worry less about power and focus more on the pleasure of kayak fishing. Remember that your fishing success depends on the reliability of your tools. So, invest wisely in your choice of batteries to reap fruitful returns in fishing productivity.