As we move further into the 21st century technology continues to evolve in ways we would have never imagined. One big advancement over the years has been the rechargeable battery. Because of these improvements battery operated electronics and propulsion systems have become more advanced, more powerful and a necessity on every watercraft and RV.
These days we need a battery that is light, has a long-lasting charge, can take thousands of repeated draw downs, and doesn’t break the bank! This article will help you understand what is the best rechargeable battery (as of today) for your fish finder, kayak trolling motor or other RV electronics.
Common Rechargeable Batteries On The Market Today
- Lead Acid – Powerful, hardy and cheap. But they are bulky, heavy and toxic.
- Nickel-Cadmium (NiCd) – Powerful but don’t hold a charge for very long.
- Nickel-Metal Hydride (NiMH) – Better than NiCd but not very practical for larger electronics, pumps and motors.
- Lithium-Ion (Li-ion) – Li-ion is now the most common rechargeable battery for portable electronics. They are light, produce high voltage and have a long life. The best thing is they hold a charge longer than these other batteries.
- Lithium-Ion-Phosphate (LiFePO4) – The Lithium Ion Phosphate battery is the better of the two Lithium Ion batteries as it lasts 4-5x longer and it does not pose the risk of fire or overheating like the Li-ion.
LiFePO4 Batteries Are The Best Rechargeable Battery for Fishing Electronics, Electric Boat Motors & Other Applications
Bottom line, 12v Lithium Ion Phosphate (LiFePO4) batteries are taking “charge” of the battery world. Whether you need to power your small fish finder, be the heart of your solar power backup, or run around the amusement park all day in your scooter, this will be the battery of choice.
| Amp Hrs | Possible Applications | Best Price |
|---|---|---|
| 4 Ah | Small Fish Finder, Bilge Pump | Sale Price |
| 10 Ah | Large Fish Finder, Small Scooter | Sale Price |
| 20 Ah | Bait Tank Pump 3-5 Hrs | Sale Price |
| 100 Ah | 55lb Thrust Trolling Motor On High For 2-4 Hrs | Sale Price |
| 200 Ah | Typically Items using over 200 watts | Sale Price |
| 400 Ah | When You Need Serious Power | Sale Price |
To calculate how long your battery will last, use these 3 metrics…
- Battery Ah Rating
- Depth of Discharge. (In The Case Of A LiFePO4 We Use 0.9)
- Wattage of Device
Battery running time formula that we will use: Hrs Of Runtime = Ah × 12V × 0.9 / Watts Of Device
Another way to get a ‘quick and dirty’ estimate, is to divide the amp draw of the device into the Ah of the battery. So if your device draws 1 amp per hour then using a 10 Ah battery you should get roughly 10 hrs of use (likely an hour or two less due to other factors).
Lithium Ion Phosphate vs. Lithium Ion Batteries
The LiFePO4 rechargeable battery is terrific for things like kayak propulsion, bass boat electronics, solar energy systems, and more. One of the biggest advantages is the life of a LiFePO4 battery is over 4-5x that of basic lithium ion batteries.
This battery is built to last for around 5,000 recharge cycles. That’s around 10 years of utilization. So, while you might pay a little more up front, the return on your investment is much better. In addition, these batteries can reach 100% depletion over and over. This is very important as some batteries like AGM will be damaged if drawn down beyond 50% or so.
LiFePO4 batteries are also the safest lithium battery type on the market. The Li-ion is known to overheat and even catch fire. LiFePO4 has overcome this issue.
Lithium Ion Phosphate Rechargeable Batteries Are Safer For The Environment
A big benefit for the environment is the long life of this battery. Of course, you will want to recycle your battery at end of life, but you won’t need to do that for a long, long time since they last up to 5000 cycles. For example, lead acid batteries last around 300-400 charges, these can be recharged up to 5,000 times!
Unlike lead acid, nickel oxide, and others, LiFePO4 batteries are non-toxic and won’t leak. They are zero maintenance as well. All of these characteristics benefit the environment.
Smaller and Lightweight
Being around 50% lighter than lithium manganese oxide batteries and up to 70% lighter than lead acid batteries you can begin to see the reasons why this battery is so popular.
In addition to being lighter they are also smaller in overall size. When you use your LiFePO4 battery in a kayak, bass boat or RV you can free up precious space as well as lighten the load.
LiFePO4 delivers Greater Efficiency and Performance
You’re a demanding consumer. You require safe, non-toxic batteries. You don’t want to lug around a ton of weight or lose valuable space. Above all, you want top performance in all areas.
- Longer runtime than other batteries.
- Fast Charging – you can obtain a full charge in 2 hours or less.
- Low Self-discharge rate – Only 2% per month discharge rate when sitting on the shelf. Other batteries like lead acid discharge at 20-30%
- Consistent power even when below 50% battery charge and beyond 50% overall battery life.
- Of course, no maintenance.
LiFePO4 Batteries vs Other Rechargeable Batteries
Lead Acid Batteries
These batteries are cheap at the counter, but they are expensive in the long run. Typical lead acid batteries often need periodic maintenance. If you miss it, you could ruin the battery. Because they do not last as long and cannot stand many full drawdowns, they end up being replaced more often. Being made of lead, they are very heavy. A LiFePO4 battery can last 2-4x longer, be 1/3 the weight and have zero upkeep.
AGM Batteries
Draining an AGM battery past 50% can cause damage and limit charges in the future. LiFePO4 batteries can be 100% discharged on a regular basis and there are no issues to worry about. AGM batteries have shorter life spans and cost about the same.
Gel Batteries
Gel batteries don’t need frequent recharging like LiFePO4 batteries. While stored, gel batteries don’t lose much of their charge either. Gel and Lithium-Ion Phosphate batteries are different in the charging process. It takes a long time for Gel batteries to charge up. To avoid ruining them, you must disconnect them when fully charged. Who needs that on their mind?
Lithium-Ion Phosphate Batteries – Beneficial For A Wide Variety Of Applications
- Fishing boats and kayaks: Longer lasting charge and shorter charge time means more time fishing. Speed and weight can be important. No one wants to paddle a heavy kayak or lose space to big lead acid batteries.
- Solar systems: Heading out into the wilderness or across the country? Light LiFePO4 batteries go where you go. They are smaller and lighter to move around and haul in your vehicle.
- Mopeds and mobility scooters: Don’t be slowed down because of unnecessary weight. Charge to less than full capacity for last minute trips and run around town until the last amp is exhausted without damaging your battery.
- Industrial use: These batteries are the safest, toughest lithium batteries out there. They are great for commercial use like liftgates, floor machines, and other machines.
Conclusion
Rechargeable Lithium Ion Phosphate batteries are the best choice for most applications
- Only slightly more expensive than poor performing batteries
- Up to 5x the life of other batteries
- About half the weight of Li-ion batteries
- About 1/3 the weight of similar lead acid batteries
- More power and stability, not likely to overheat or catch fire
- More environmentally friendly than other battery types
