48V Battery and Charger Guide: Sizing, Charging, Replacing

Every StepRanger All-Terrain runs on the same 48V power system: four sealed AGM deep-cycle batteries and a compact charger that plugs into any 110V household outlet. The system is simple on purpose. No fuel, no oil, no proprietary charging station. This guide covers how the pack is sized, how to charge it correctly, when a second battery set or a second charger earns its keep, and how to tell a battery that needs replacing from one that just needs recovering.

If you're new to the machine itself, start with What is an electric micro-truck? This guide is for owners, and for anyone sizing a battery setup before ordering.

How the 48V pack is built

The pack is four 12-volt, 25 amp-hour sealed AGM deep-cycle batteries wired in series. Four 12V batteries in series make 48 volts, and the pack keeps the 25Ah rating. That works out to roughly 1.2 kWh of stored energy. Each battery weighs about 14 lb, so a full set runs about 57 lb.

A single pack moves the All-Terrain 15-17 miles on a charge. The dual-battery option adds a second four-battery set in parallel: the system stays at 48 volts, capacity doubles to 50Ah (roughly 2.4 kWh), and range roughly doubles to 30-34 miles.

These are deep-cycle traction batteries, built to be drained and recharged day after day. They're not car starting batteries, and they're not lithium. Sealed AGM ships without hazmat restrictions, winters in an unheated shed without complaint, charges from a plain wall outlet, and a replacement set is inexpensive next to any lithium pack. For a work machine that lives in a barn, that's the practical choice.

One battery set or two

The dual-battery decision is about more than range. Sealed AGM lifespan is set mostly by depth of discharge, meaning how far down you run the pack before recharging. Our cell data puts it at 400-600 cycles when the pack is routinely run flat, and 1,200+ cycles when you recharge around the halfway point. Same batteries, roughly double the working life.

That's why we tell owners to plan the workday around about half the rated range, call it 7-8 miles on a single set. If your day regularly runs past that, a second set doesn't just extend range. It moves the same workload into the shallow-discharge zone that doubles battery life.

• Single set: occasional hauling, short loops, a property measured in a few acres. (For the trip math on a typical parcel, see the 5-acre hauler guide.)
• Dual set: all-day work like barn chores, long perimeter runs, or winter use. Cold trims lead-acid capacity to about 85% at freezing and about 72% in single digits, so a dual set is what keeps a full winter workday on one charge.
• Accessory loads: if you run an inverter, winch, or 12V accessories regularly, go dual. A single bank comfortably supports roughly 600 watts of continuous accessory draw, and a dual bank doubles that headroom.

Charging: how it works and how to do it right

The included charger outputs 48V at 2.8 amps and runs on 110V household power. A typical recharge takes 5-6 hours, and a fully drained pack finishes overnight. The charge port is on the left side of the truck. Trucks arrive at 80-100% charge, so you can drive first and charge later.

Chargers for sealed lead-acid work in three stages: bulk (most of the charge), absorption (the top-off), and float (holding full). The charger handles all of that on its own. Plug it in and let it finish. What you should manage:

• Use the matched 48V charger. Sealed batteries are voltage-sensitive, and a charger with the wrong setpoints can permanently damage the pack. A spare 48V charger is simple insurance against borrowing the wrong one.
• Never equalize. Equalizing charges are for flooded batteries. On sealed AGM the gas has nowhere to go, and the battery dries out. If a charger has an equalize mode, don't use it on this pack.
• Charge between 32°F and 104°F. Below freezing, wait or move the truck somewhere warmer.
• Charge after a good day of use, and never store it drained. There's no need to leave it plugged in between short runs, and no need to top off after every trip. Sitting fully discharged is what kills sealed lead-acid.

Dual sets: one charger works, two chargers are faster

A dual-battery truck charges fine with the standard routine: leave both battery-bank switches up and one charger fills both sets through the parallel link. It just takes about twice as long, because the same 2.8 amps now feeds double the capacity.

Our recommendation for dual-set owners is a second charger. Flip both bank switches down and charge each side independently, and the job runs in half the time. It's also good practice to charge the two banks to full independently every so often, so the sets stay in sync. Flip both switches back up to drive.

Replacing: recover first, then replace as a set

When a sealed AGM pack is wearing out, the signs are consistent. The pack charges to full but fades noticeably faster than it used to. The truck sags hard under load on grades it used to pull. Or a battery case is swollen, hot to the touch after charging, or venting an odor. Those physical signs mean stop using the pack and contact us.

Before you order anything, though: a pack that won't take a charge is not necessarily dead. A deeply discharged AGM pack can often be recovered, and we'd rather walk you through recovery than sell you a set you didn't need. Call or email first. If a pack truly won't come back, it's covered under the 2-year warranty.

When you do replace, a 48V battery replacement means the full string: a matched set of four, not one battery at a time. In a series string the weakest battery caps the whole pack, and mixing an old battery with new ones drags the new ones down and wears everything out faster. It's the same reason golf-cart packs are replaced as a set. The 48V battery set is the same four-battery pack the truck shipped with, and it fits both the All-Terrain and the Pro 48V.

If you add a second set later to make a dual-battery truck, order it as soon as you can after the first. Paralleled banks pull each other toward the same state of charge, so a fresh set paired with a well-worn one does more than its share of the work. The 48V banks have their own switches, so you can charge them independently and keep them in sync, but the closer the two sets are in age, the longer both last. Ordering dual at purchase is the cleanest version of this.

Storage and winter

• Charge to 100% before lay-up.
• Flip the battery switch(es) off. That fully isolates the pack, so nothing draws it down.
• Leave the batteries in the truck. AGM handles cold storage without damage, and there's no reason to haul four 14 lb batteries indoors.
• On the shelf, the pack self-discharges to about 90% at three months, 80% at six, and 60% at nine. Top off in spring, or mid-winter on a long lay-up.
• Leaving the charger connected for the season is an option only if the space stays above freezing. The charger doesn't operate below 32°F.

Five rules that protect the pack

1. Never let it sit drained. Charge after a good day of use.
2. Never pull 12V off one battery in the string. That unbalances the series pack, damages it, and isn't covered under warranty. Run accessories through a 48V-to-12V converter wired to the full pack on its own fused circuit.
3. Keep continuous accessory draw to roughly 600 watts on a single bank.
4. Rain is fine. Pressure-washing into the battery box is not.
5. Use the matched charger, inside the 32-104°F window, and skip equalize modes entirely.

A note on the Pro 60V

The Pro 60V, our current-generation model, runs the same sealed AGM chemistry as the All-Terrain, with five 12V batteries in series instead of four. Everything in this guide about depth of discharge, charging habits, cold weather, storage, equalize modes, and replacing batteries as a matched set applies to it directly. What does not carry over: the pack is 60V, it uses its own 60V charger and 60V battery set (both on the Pro 60V product page), and both battery boxes share a single breaker and a single charge port, so there are no per-bank switches to flip and a dual set always charges as one bank. Any 12V accessory on a Pro 60V needs a 60V-to-12V converter wired to the full pack, never a tap off one battery.

Who builds it

StepRanger designed the All-Terrain form factor and introduced it to the US market in 2023, selling regionally in California and Montana before taking the truck nationwide in May 2025. We're founder-led, headquartered in California with a second location in Montana, and we work directly with our factories rather than through trading companies. A co-founder has averaged at least one factory visit a month going back several years, and an independent engineer is onsite overseeing production. The All-Terrain holds 4.9 stars across 180+ third-party-verified reviews, all published, and every truck carries a 2-year warranty. When you call or email, a co-founder answers.

Questions this guide didn't cover are probably on the FAQ, and you can reach us through the locations page. If you're sizing a battery setup ahead of an order, the All-Terrain product page always shows the current configuration options.

Ready to see the full specs and current pricing? StepRanger Pro 60V or StepRanger All-Terrain.