Why you should try lithium for marine
Whether you're a commercial fisherman, captain, compete in fishing tournaments regularly, or simply just enjoy going out to the sandbar on the weekends, you probably realize that the number one problem when boating is having a reliable battery.
For years, lead-acid and AGM batteries have dominated the marine industry because they're readily available, cheap, and easily replaceable. The issue is that these batteries don’t hold a charge for very long, are prone to acid leakage, and generally weigh down water vessels a considerable amount. Lithium batteries have considerable advantages over conventional wet lead acid, absorbed glass mat (AGM) and sealed Gel marine deep cycle batteries. The most significant of these benefits is longer lasting power
Advantages of Lithium Batteries
1. Need Fewer Amp-Hours
Lithium batteries can be discharged 100%, although 80% is better for them long-term. So you don’t need nearly as large a battery bank.
2. Lighter Weight
Lithium batteries also weigh considerably less than any batteries used on a boat. Our new lithium batteries weigh about half what the deep cycle lead acid batteries did. That’s nice for the weight of the boat, but the bigger deal might just be in trying to move them in and out of the battery compartment.
3. Higher Resting Voltage
Full charged lead acid batteries will “rest” at 12.6 to 12.8 volts. As a load is placed on them and also as they are discharged, the voltage will drop. Consequently, things like refrigerators, watermakers, microwaves and inverters do not run as efficiently and end up drawing more amps, causing a downward spiral.Lithium batteries rest at 13.2 volts and that doesn’t particularly change with the load placed on them or how far discharged they are. Our refrigerator takes about 10% fewer amps when running; our watermaker puts out more water in the same amount of time.
4. Can Run Heavy Loads on Lithium Batteries
Lithium batteries can put out a lot of amps with no damage to the batteries, unlike deep cycle lead acid batteries. Lead acids simply can’t keep pumping out the amps and maintain the voltage.
5. Much Faster Charging
Lithium batteries can take higher charging amps for a far higher percentage of their capacity than lead-acid batteries.
6. No Wasted Energy
Another charging advantage of lithium batteries is that you can get out 99% of the energy you put into them, versus about 85% with lead acid batteries (and the percentage drops each year). This equates to getting about 15% more out of your charging sources. For us, that’s like adding another 50 watt solar panel to our existing 345 watts. If you use a generator, it takes another 15% off the generator run time.
For us, the longer lifespan, greater usable amp-hours and lighter weight of lithium batteries are the best-known benefits but just the start. The better charging profile has made a huge difference in our lives. The ability to run larger loads through an inverter instead of the generator will be nice when we have the need. The ability to use the windlass without the engine or generator running may someday allow us to get out of an untenable anchorage in 3-foot seas and a dead engine. Yes, the lithium batteries were expensive but we’re avoiding the cost of another solar panel and regulator and/or the cost of running the generator.
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