Battery maintenance means charging and storing each battery type the right way for its chemistry: lead-acid, AGM, and gel batteries want a float charge to stay topped off, while lithium batteries charge fast, hold their charge for months, and should never be float-charged. In this How 2 Tuesday I bring in Joe Cubberley of Lithium Pros to walk through every type, why I moved my boat to lithium, and how to keep each one alive and ready.
Listen now: press play in the player above and follow along.
Each chemistry is charged differently. Lead-acid, AGM, and gel batteries benefit from a maintenance or float charge to stay topped off, and you only get about 50 percent of their rated capacity in usable power. Lithium charges much faster, uses close to 100 percent of its capacity, and should not be float-charged because it does not like the high voltage and does not need it. Joe Cubberley breaks down the right approach for each in the episode.
Weight, charge speed, and run time. The heaviest Lithium Pros unit is around 38 pounds versus roughly 210 pounds for my old lead setup, which is huge on a weight-sensitive skiff. Lithium charges fast, mounts anywhere, runs at basically full power until it is empty, and is rated for thousands of cycles with a ten-year warranty. I get into the whole comparison with Joe in the episode.
No. Lithium does not like the high voltage of a float charge and does not need it. It holds its charge for months, so the right move is to fully charge it before you leave, make sure your kill switches are off so there is no draw, and it will be ready six months later. Lead-acid, by contrast, can drop around 30 percent just sitting. Joe explains safe lithium storage in the episode.
A cycle is one full charge to discharge. Lithium Pros tests down to an 80 percent discharge state and rates its batteries at 3,000 to 5,000 cycles, while lead-acid only gives you about 50 percent usable discharge and far fewer cycles. A battery that charges fast also saves wear on your onboard charger, so lithium pays off twice. Joe details how he counts cycles honestly in the episode.
Lithium delivers close to full power right up until it suddenly drops, similar to a cordless drill, then a built-in battery management system puts it into a protective safe mode or shutoff to protect the battery and your equipment. To reset it you turn the switch off and on or disconnect the terminal for about 15 seconds. Monitoring tools like the Sea Monster app show real-time percentages so you are never caught off guard. Joe explains the BMS in the episode.
I have leaned harder on my trolling motor every year, running it on high inshore and offshore all day, and the challenge is doing that without killing my batteries. This year I think I finally cracked it with a Power-Pole on-the-go charger and Lithium Pros batteries. Every battery type charges differently, though, and I wanted to do it right, especially for storage. Joe Cubberley knows more about batteries than anyone I have met, he even drove 14 hours once to diagnose a loose-cable issue on my boat, so I brought him on to set the record straight. Hear him in the episode, so press play in the player above.
On a skiff, every pound in the bow matters, and the weight difference with lithium is staggering. My old lead-acid setup ran around 210 pounds, while the heaviest Lithium Pros unit is about 38 pounds. Putting 30 to 40 pounds up front instead of 210 transformed how the boat runs. Joe explains why lithium packs so much more energy into so little weight in the episode, so press play in the player above.
A cycle is a full charge to discharge, and this is where the chemistries split. Lead-acid gives you only about 50 percent usable discharge and a limited number of cycles. Lithium Pros tests down to an 80 percent discharge and rates 3,000 to 5,000 cycles, backed by a ten-year warranty because they have batteries over ten years old still in the field. Joe explains how some makers play cycle games in the episode, so press play in the player above.
The Power-Pole charger transfers voltage and charges while the boat runs. It feeds the crank battery first so you always get home, then the house battery, then tops off the 36-volt trolling-motor batteries one at a time. With lithium charging so fast, an hour or hour-and-a-half run back can put around 20 percent back into the trolling batteries. I walk through my setup with Joe in the episode, so press play in the player above.
Storage is where people kill batteries. Lead-acid, AGM, and gel like a maintenance charge, but lithium is different, do not float-charge it. Fully charge it, kill any draw with your switches, and it holds for months. Leaving a cheap clip-on charger plugged in for weeks is actually a fire risk, which is another reason lithium's no-float storage is better. Joe lays out safe storage for each type in the episode, so press play in the player above.
After years of fighting dead batteries, the combination of lithium and an on-the-go charger has made my trolling-motor setup near impossible to kill. The bigger lesson from Joe, though, is that every chemistry wants to be treated differently.
Whatever you run, match your charging and storage to the battery, do not float-charge lithium, and keep an eye on your voltage so you always get home. Press play in the player above for Joe's full breakdown.
Joe Cubberley · Lithium Pros · Power-Pole · Sea Monster app · lead-acid batteries · AGM batteries · gel batteries · lithium batteries · trolling motor · battery management system · How 2 Tuesday · Tom Rowland Podcast
How 2 Tuesday is my weekly series where I break down one fishing skill at a time, from knots and casting to gear, tactics, and the habits that make you a better angler. Watch and listen to every How 2 Tuesday episode from Tom Rowland.
Joe Cubberley of Lithium Pros is a battery expert known for his deep knowledge of lead-acid, AGM, gel, and lithium chemistries and for his hands-on customer service. He has spent years helping anglers and boaters build reliable, lightweight power systems, and he breaks down the technical details in language any boater can put to use.
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