X2Power represents one of the leading brands in marine lithium batteries, and we gave one of its models a season-long test in a G3 V167T aluminum boat, fishing the lakes of central Michigan. It was a 31-series 100-amp-hour, 12-volt deep-cycle battery featuring lithium-iron-phosphate (LiFePO4) chemistry ($899.99; batteriesplus.com). In this test, we dedicated it to powering a Minn Kota PowerDrive 12-volt trolling motor with Spot-Lock.
We were delighted with several facets, including the light weight of 28.2 pounds (about 50 percent less than a comparable lead-acid battery), power delivery (it ran for two to three days without fading or needing a recharge), the fast-charging characteristics (it charged about four times faster than the old lead-acid battery), and the five-year free-replacement warranty.
We tested the battery in conjunction with the X2Power 7.5-amp battery charger ($129.99; batteriesplus.com), which did a great job of quickly bringing the battery to full potency once we set the charge mode to “lithium.” It can charge flooded-cell, gel and AGM lead-acid batteries as well.
Read Next: Installing a Lithium Battery System
Some X2Power batteries are now Bluetooth-enabled, allowing you to monitor state of charge and other functions with the X2Power app. Our test battery did not include the app, but we installed a Victon Energy SmartShunt 500-amp Bluetooth battery monitor ($130.90; amazon.com) to monitor the state of charge.
One caveat: These deep-cycle batteries are not for use as cranking batteries and should be completely isolated from the engine-cranking circuit. Applications are limited to circuits for equipment such as trolling motors and marine electronics. Visit x2powerbattery.com to learn more.