Only a little. The charge wire in most 7-pin connectors is small, so it trickles power to your trailer rather than recharging it. And a lithium battery should only connect to an alternator whose output tops out at 14.6V or below. A DC-to-DC charger is the usual fix: it takes power from your tow vehicle and charges the trailer battery at the right voltage. Millertech carries 12V 10A (1210DC-DC) and 12V 20A (1220DC-DC) DC-to-DC chargers.

Yes. Keep a charged Max 8.0 and its hub in the house, and you can keep phones and tablets running when the power goes out. It’s also a quiet way to charge USB devices at an off-grid homestead, in a cabin or in a tiny home.

Yes. It can charge from a solar panel while it powers your camera, using the Two-Way Splitter (Item #1117-SP), sold separately. Keep the solar panel's output at or below 12.6V and 5A (63W).

Yes, with the Dark Speed "On The Run" charger. While your outboard runs, it uses the alternator to charge your 12V cranking battery first. It then sends extra power to your 24V or 36V trolling motor battery. That can add hours to your day without shore power or a generator. It comes in 12V/24V (DS24) and 12V/36V (DS36) models.

Yes, you can discharge the battery down to 0%. When it reaches 0%, it will enter low voltage protection (sleep mode). To recharge, simply connect a lithium-approved charger, which will wake up the battery and begin charging it again.

It may work, but it could overcharge your battery, or it may not have enough voltage to charge it fully. Before you hook it up, call Millertech at 855-MAX-LITH. A real person will tell you whether your charger is compatible with your batteries. We'll never try to sell you something you don't need. When our customers have exactly what they need and nothing else, they're happy, and that's what makes us happy.

Both the Max 4.0 and the Max 8.0 have a built-in battery usage meter.

From empty to full with the included 2A charger, the Max 8.0 takes about 14 hours and the Max 4.0 takes about seven hours.

Divide the battery's amp hours (Ah) by the charger's amps. A 100Ah battery takes 10 hours to charge from empty with a 10A charger, or five hours with a 20A charger.

Divide your battery's amp hours (Ah) by your charger's amps. A 100Ah battery takes 10 hours to charge from empty with a 10A charger, or five hours with a 20A charger.

Up to eight on the Max 8.0 hub (four USB-A and four USB-C) and up to four on the Max 4.0 hub (two of each). That’s enough to keep the whole group’s phones charged at camp.

The Max 8.0 gives you roughly 15 to 20 full charges for a typical smartphone, or four to five for a mid-size laptop. The Max 4.0 gives you about half that. Those numbers assume a completely dead device charged all the way to full.