Lithium (LiFePO4) trolling motor batteries are lighter and last longer than lead-acid ones, but they need a charger that knows it's charging lithium. Not every DualPRO does. Here is which DualPRO models charge lithium, how they differ, and what to do on a boat that runs lithium and AGM side by side.
Which DualPRO chargers charge lithium
| DualPRO model | Lithium? | How the battery type is set |
|---|---|---|
| Professional Series standard: PS1, PS2, PS3, PS4 | No. DualPRO lists them for wet cell and AGM | Not applicable |
| Professional Series AutoProfile: PS1AUTO, PS2AUTO, PS3AUTO, PS4AUTO | Yes | Automatic: detects lithium, AGM or flooded on each bank |
| Sportsman HF: SS2HF, SS3HF, SS4HF | Yes | You select lithium, wet cell or AGM for each bank |
| Eagle HF ES800 marine: ES0800-24V003, ES0800-36V003, ES0800-48V003 | Yes | You choose the algorithm in the free PROView Link app |
AutoProfile: nothing to set
DualPRO's AutoProfile reads each battery when it's connected, works out whether it's lithium or AGM, and applies the charge profile that chemistry needs. It also detects and charges flooded (wet cell) batteries. Because the detection happens per bank, a PS3AUTO can charge two lithium trolling batteries and an AGM cranking battery at the same time, each on its own profile. If you later swap the AGM for lithium, there's nothing to reprogram.
DualPRO's PS3AUTO and PS4AUTO pages also list a lithium wake-up feature, which revives a lithium pack that has shut itself off through its BMS low-voltage protection, and an automatic return-to-charge that keeps batteries maintained without overcharging.
Sportsman HF: you choose per bank
The Sportsman HF does the same job with a manual setting. You configure each bank for lithium (LiFePO4), wet cell or AGM to match the battery on it. It's a good fit if you know exactly what's on the boat and you want a lighter, smaller charger: 10A per bank against 15A for the Professional Series. See the full comparison in Professional Series vs Sportsman HF.
Switching from AGM to lithium?
If your boat already has a standard (PROVolt) Professional Series charger, DualPRO lists that model for wet cell and AGM batteries. Moving to lithium means moving to an AutoProfile or Sportsman HF model, or another charger your battery maker approves. Before you buy, check your lithium battery maker's charging requirements. DualPRO says it works with lithium battery manufacturers to develop and validate its charging algorithms, and the battery's own manual is the final word on charge voltages and temperature limits.
One 24V, 36V or 48V lithium pack
Many lithium trolling setups use a single 24V or 36V battery instead of two or three 12V batteries in series. Professional Series and Sportsman HF banks are 12V outputs, so they suit 12V batteries. For a single higher-voltage pack, look at the Eagle HF ES800 marine chargers: 800W, IP67, with the lithium, AGM or lead-acid algorithm chosen in the PROView Link app. Details in our Eagle HF ES800 guide.
A worked example: 36V lithium trolling motor plus an AGM cranking battery
Say the trolling motor runs on three 12V lithium batteries wired in series for 36V, and the outboard starts from one 12V AGM battery. That's four 12V batteries, so you need four banks:
- With a PS4AUTO: connect one bank to each battery. AutoProfile detects the three lithium batteries and the AGM battery and charges each on its own profile at up to 15A.
- With an SS4HF: connect the same way, then set banks one to three to lithium and bank four to AGM. Each bank charges at up to 10A.
If the same boat runs one 36V lithium battery instead of three 12V batteries, the multi-bank chargers don't fit. Use the 36V Eagle HF ES800 marine version, ES0800-36V003, and set lithium in the app.
Day-to-day charging
- Leave it plugged in. DualPRO's chargers are fully automatic, and DualPRO's PS3AUTO and PS4AUTO pages describe an automatic return-to-charge that keeps batteries topped up without overcharging.
- Battery won't wake up? If a lithium battery has shut itself off at low voltage, DualPRO's PS3AUTO and PS4AUTO pages describe a wake-up feature for exactly that. With other chargers, follow the battery maker's instructions.
- Watch the lights. LEDs show the state of charge on each bank, and diagnostic codes flag a bank that has a problem.
Know how much is left
Lithium batteries hold a nearly flat voltage until they're close to empty, so a simple voltage gauge can't tell you much. DualPRO's lithium fuel gauges use a current transducer that counts amp-hours in and out. See which DualPRO lithium battery gauge fits, or our guide to SmartShunt for lithium trolling motor batteries for the shunt-and-app alternative.
FAQ
Will a DualPRO AutoProfile charge an AGM cranking battery and lithium trolling batteries together?
Yes. Detection is per bank, so each battery gets the profile for its own chemistry.
Is the Sportsman HF lithium ready out of the box?
It supports lithium, but you set each bank to lithium yourself. It doesn't detect the chemistry automatically.
Do I need to change any settings when I swap a battery?
On an AutoProfile model, no: it detects the new battery when it's connected. On a Sportsman HF, yes: set that bank to the new battery's chemistry before charging.
Does the one-bank PS1AUTO have AutoProfile too?
Yes. The PS1AUTO uses the same AutoProfile detection on its single 15A bank, so it suits a boat with one 12V lithium battery.
Which bank count do I need?
One bank per 12V battery you want to charge. Our guide which DualPRO charger do I need has the table.
Shop the DualPRO range or browse LiFePO4 lithium batteries.