What Size Lithium Battery for 36V Trolling Motor？
A 36V high-thrust marine trolling motor is commonly used on mid-size bass boats, recreational fishing boats, aluminum deep-V boats, and tournament fishing boats. Compared with 24V motors, it delivers more power and requires stronger battery discharge performance and longer runtime.
Choosing the right battery capacity is essential. A battery that is too small may leave you short on power, while an oversized or low-quality battery can add unnecessary cost and weight. Power Queen offers three mainstream 36V marine lithium battery options—45Ah, 50Ah, and 100Ah—covering everything from short casual trips to full-day fishing and high-intensity tournament use.
Quick Answer
For most 36V marine trolling motors rated around 100–120 lbs of thrust, the ideal lithium battery capacity depends on your boat size, fishing duration, onboard electronics, and how hard you run the motor.
Power Queen currently offers three mainstream 36V lithium battery options for marine use:
| Battery Model | Usable Energy | Best For | Typical Runtime |
|---|---|---|---|
| 36V 45Ah | 1,728Wh | Short trips, lightweight boats, casual fishing | 3–6 hours |
| 36V 50Ah | 1,920Wh | Half-day fishing, small to mid-size boats | 4–7 hours |
| 36V 100Ah | 3,840Wh | Full-day fishing, tournaments, heavy-duty marine use | 8–14 hours |
For short recreational fishing trips, a 36V 45Ah or 50Ah lithium battery is usually enough. For full-day fishing, professional tournaments, rough waters, or boats with multiple electronic devices, the 36V 100Ah battery is the best long-term choice.
Two Ways to Power a 36V Trolling Motor
There are two common ways to build a 36V battery system for a marine trolling motor: using one integrated 36V lithium battery or connecting three 12V batteries in series.
| Power Setup | Key Advantages | Things to Consider |
|---|---|---|
| One integrated 36V lithium battery | Less wiring, built-in BMS, saves space, easier charging, better cell balance, more stable long-term marine power supply | Higher upfront cost; if the battery fails, the whole unit may need to be replaced |
| Three 12V batteries in series | Flexible battery placement; a single failed battery can be replaced separately | All three batteries must match in capacity, brand, function, and condition. Mixing old and new batteries can easily cause voltage imbalance and reduced runtime. |
Most serious tournament anglers prefer a Power Queen integrated 36V lithium battery. It reduces wiring clutter inside the battery compartment and provides more stable voltage output during long periods of spot-locking, anchoring, and high-load operation.
Common Lithium Battery Sizes for 36V Trolling Motors
The following three models are Power Queen’s standard production models. They are not niche custom batteries and are suitable for most civilian, recreational, and professional fishing applications.
| Battery Model | Usable Energy | Suitable Boats | Recommended Use | Typical Runtime |
|---|---|---|---|---|
| 36V 45Ah | 1,728Wh | Jon boats, deep-V aluminum boats, small to mid-size bass boats | Short fishing trips, lightweight setups, basic onboard equipment | 3–6 hours |
| 36V 50Ah | 1,920Wh | Small to mid-size recreational boats, deep-V aluminum boats, small to mid-size bass boats | Half-day fishing, basic fish finder setups | 4–7 hours |
| 36V 100Ah | 3,840Wh | Mid-size bass boats, professional fishing boats, multi-purpose fishing boats | Full-day fishing, multiple electronics, tournaments, complex water conditions | 8–14 hours |
Please note that runtime is an estimate based on battery capacity and the motor’s operating current. Actual runtime may vary depending on water current, wind speed, boat load, thrust level, and onboard power consumption.
Power Queen 36V 45Ah Lithium Battery for Lightweight Setups
The Power Queen 36V 45Ah battery is designed for lightweight performance and excellent value. It is compact and much lighter than traditional lead-acid batteries, helping reduce overall boat weight.
It features a smart 90A BMS for comprehensive safety protection, Bluetooth 5.0 real-time monitoring, and support for multiple charging methods. With a service life of up to 10 years and a maintenance-free design, it is a strong choice for small boats and short casual fishing trips.
![[Like New] Power Queen 36V 45Ah Golf Cart Smart GC2 Lithium Battery - Power Queen US](http://ipowerqueen.com/cdn/shop/files/PQ-38.4V45Ah-BT-AGC2_0270d06a-956c-4448-88a3-52d5a45dcc8f.jpg?crop=center&format=webp&v=1767669425&width=400)
Power Queen 36V 50Ah Lithium Battery for Half-Day Fishing
The 36V 50Ah model is one of Power Queen’s key marine battery options and is well suited for nearshore recreational fishing.
It comes with an intelligent BMS, low-temperature cut-off protection, Bluetooth monitoring, and parallel expansion support. It offers stable performance, a long cycle life, and a 5-year official warranty, making it a mainstream choice for small to mid-size fishing boats.
For example, if you usually fish for half a day on a calm Texas reservoir with a small to mid-size bass boat, a 36V 45Ah or 50Ah lithium battery may be enough for your regular trips.
![[Used - Very - Good] Power Queen 36V 50Ah Smart Deep Cycle Lithium Battery - Power Queen US](http://ipowerqueen.com/cdn/shop/files/PQ-38.4V50Ah-TM-BT-A100_9262863d-8cfc-4660-8fc3-34e2ffcea0a1.jpg?crop=center&format=webp&v=1767677936&width=400)
Power Queen 36V 100Ah Lithium Battery for Maximum Runtime
The 36V 100Ah model is Power Queen’s flagship high-capacity marine battery. It delivers stable high-power output and is built for challenging marine conditions, including wind, waves, heavy loads, and extended trolling motor use.
It features an IP65 waterproof and dustproof rating, salt spray resistance, multiple BMS protections, and smart low-temperature protection. Compatible with many premium trolling motor brands, this battery is designed for full-day, high-intensity professional fishing trips.
On larger and windier waters like Lake Erie, the trolling motor often has to work harder against waves, current, and wind. In that case, choosing a higher-capacity battery gives you a safer margin and helps avoid running out of power before heading back.
LiFePO4 Battery vs. Traditional Lead-Acid Battery
According to the U.S. Department of Energy’s Alternative Fuels Data Center, lithium-ion batteries are widely used in electric-drive applications because they offer high energy density and strong power output. This is one reason lithium batteries are increasingly preferred over traditional lead-acid batteries for marine trolling motor setups.
| Feature | LiFePO4 Battery | Lead-Acid Battery |
|---|---|---|
| Weight | Lightweight | Heavy |
| Usable Capacity | Nearly 100% | About 50% |
| Charging Speed | Supports fast charging | Slow charging |
| Voltage Stability | Holds voltage more steadily | Voltage drops continuously |
| Cycle Life | 4,000+ cycles | 200–500 cycles |
| Service Life | Up to 10 years | 2–3 years |
Power Queen LiFePO4 batteries offer stable discharge performance, intelligent safety protection, long service life, Bluetooth monitoring, low-temperature protection, waterproof protection, and salt spray resistance. These features make them especially suitable for humid, variable, and demanding marine environments.
Over the long term, their total cost-effectiveness is much better than traditional lead-acid batteries.
Related Blog: What Is a LiFePO4 Battery? Everything You Need to Know.
How to Estimate Trolling Motor Runtime
You can estimate marine trolling motor runtime with the following formula:
For example, if you use a 36V 100Ah battery and your trolling motor draws 45A at full speed, the theoretical runtime is:
However, most anglers do not run their trolling motor at full speed all the time. In real-world use, trolling motors are often operated at low to medium speeds, which significantly extends runtime. That is why a 36V 100Ah battery can typically support 8–14 hours of regular fishing use.
Actual runtime is affected by water resistance, wind, current, tide, motor speed setting, boat weight, and onboard electronics. For long trips or complex water conditions, it is always smart to leave extra battery capacity as a safety margin.
Common Mistakes When Choosing and Using Marine Lithium Batteries
Choosing a Low-Capacity Battery Just to Save Money
A smaller battery may cost less upfront, but it can run out of power during long trips or in rough water. Frequent high-load discharge can also accelerate battery wear, increasing replacement costs over time.
Looking Only at Capacity and Ignoring Discharge Performance
A 36V high-thrust trolling motor requires strong continuous discharge capability. If the battery cannot provide enough current, it may trigger overcurrent protection, shut down suddenly, or affect boating safety.
Using the Wrong Charger
Lithium batteries and lead-acid batteries use different charging profiles. Using a standard lead-acid charger with a lithium battery may cause abnormal charging, cell damage, shortened lifespan, or even battery failure.
Mixing Old and New 12V Batteries in Series
When using three 12V batteries in series, all batteries should match in brand, capacity, age, condition, and function. Mixing different batteries can cause voltage imbalance. The total usable capacity of the system will be limited by the weakest battery.
Storing the Battery Fully Charged or Deeply Discharged for Long Periods
Long-term storage at full charge or very low charge can reduce cell activity and cause irreversible capacity loss.
Charging and Maintenance Tips for Marine Lithium Batteries
Proper charging and maintenance can greatly extend the service life of your marine lithium battery and help ensure stable long-term performance.
Use a Dedicated Lithium Battery Charger
A 36V LiFePO4 battery must be charged with a compatible lithium battery charger. Do not use a lead-acid charger. Always make sure the charger’s voltage and charging profile match the battery specifications to prevent cell damage or battery failure.
Recharge After Each Fishing Trip
Recharge the battery after every fishing trip. Avoid storing it for long periods in a deeply discharged state, as this helps maintain cell activity and extend battery life.
Store the Battery Properly When Not in Use
If the battery will not be used for an extended period, disconnect all onboard devices and store the battery at around 50% charge. Keep it in a cool, dry, well-ventilated place away from heat, moisture, and salt spray.
Check Battery Status Regularly
Use the built-in Bluetooth function and the Power Queen app to monitor voltage, state of charge, temperature, and other key data. If anything looks abnormal, troubleshoot promptly or contact Power Queen customer support.
FAQ
Q1: How long will a 36V 100Ah lithium battery last?
Under normal low-to-medium-speed cruising conditions, a 36V 100Ah lithium battery can typically provide 8–14 hours of runtime, enough for full-day fishing.
Q2: Can three 12V batteries in series replace one integrated 36V lithium battery?
Yes, but it is not ideal for long-term use. Mixing old and new batteries can easily cause voltage imbalance and reduced runtime. In terms of stability, safety, and convenience, an integrated Power Queen 36V lithium battery is a better solution.
Q3: Does a 36V marine lithium battery need a special charger?
Yes. Lithium batteries and lead-acid batteries have completely different charging profiles. Using the wrong charger can damage the cells, shorten battery life, or cause battery failure. A dedicated 36V lithium battery charger is required.
Q4: Do casual anglers really need a 100Ah battery?
Not always. For short recreational trips, a 36V 45Ah or 50Ah battery is usually enough. However, if you often fish all day, operate in complex water conditions, or run multiple onboard electronics, the 36V 100Ah battery offers much better runtime, stronger continuous output, and better long-term value.
Conclusion
Choosing a battery for a 36V marine trolling motor does not mean simply buying the largest capacity available. The best choice is the one that matches your boat, fishing style, runtime needs, and onboard power demand.
For short solo trips and lightweight fishing setups, the Power Queen 36V 45Ah battery is compact, practical, and cost-effective. For half-day fishing on small to mid-size boats, the 36V 50Ah marine lithium battery offers stronger overall compatibility. For full-day fishing, professional tournaments, complex waterways, and high-intensity use, the 36V 100Ah premium battery provides the best overall performance.
With Bluetooth monitoring, multiple safety protections, long cycle life, and reliable marine-grade performance, Power Queen 36V lithium batteries are an ideal power solution for 36V marine trolling motors.
