Battery Chargers for Marine Use – Marine & Boat Battery Chargers

Boat Battery Chargers, Inverters, Converters, & Isolators Resources and Information

Keeping batteries healthy is critical for safe, reliable boating. PartsVu carries onboard and portable marine battery chargers, multi-bank smart chargers, inverters, converters, and isolators from trusted brands like Samlex America, ProMariner, Xantrex, Minn Kota, Mastervolt, and more.

Looking for more boating and marine products? Check out our complete selection of Products and Accessories. You can also shop our broader selection of Electrical and Lighting Accessories for Boats or Boat Lighting Products and Accessories. Or browse our collection of marine battery chargers and accessories:

• Onboard Battery Chargers – Fixed units for charging while docked.
• Portable boat battery chargers – Lightweight, flexible options.
• Inverters and converters – Power conversion for onboard electronics.
• Isolators and combiners – Manage multiple battery banks safely.

Choosing a charger: match chemistry (Flooded/AGM/Gel/Lithium), banks (starter/house/trolling), and output. As a rule of thumb, total charger amps ≈ 10–20% of battery bank Ah (e.g., 100Ah → 10–20A). Prioritize marine-rated units (ignition-protected, corrosion-resistant), temperature compensation, and IP drip/spray protection for your install location.

Inverter = DC→AC for household loads Converter = AC→DC supply/charging Isolator/Combiner = manages multiple banks (prevents back-feeding, prioritizes start battery).

Smart profiles: 3-stage (bulk/absorption/float) covers most boats; 4-stage adds equalize (lead-acid maintenance). Lithium profiles omit equalize and rely on BMS—select a charger with a dedicated Li mode when applicable.

Brand quick take: Samlex = rugged value, clean DC output; ProMariner = boat-focused multi-bank smart chargers; Xantrex = advanced charging + system monitoring; Minn Kota = proven trolling-bank management; Mastervolt = premium networked chargers/inverter-chargers for larger systems.

Marine Battery Chargers, Inverters, Converters, and Isolators FAQs

How do I install a marine battery charger?

Mount in a dry, ventilated area with drip protection; leave 4–6″ clearance for airflow. Use tinned marine cable sized for run length and fuse each positive conductor within ~7″ of the battery (per ABYC E-11; check local code). Connect DC negatives to the boat’s DC ground bus; bond the charger chassis ground as specified. Verify polarity, select the correct battery chemistry profile, and perform a full-charge test. For model-specific diagrams, see the product manual or our Xchange install guides.

How do I maintain a marine charger?

Keep vents clear, inspect terminals for corrosion, confirm the correct chemistry mode, and test float voltage seasonally (lead-acid ~13.2–13.6V @ 77°F). Common issues: won’t enter float (bad battery/BMS or wrong profile), overheat/derate (poor airflow), no charge on one bank (fuse/open circuit).

Pricing varies by brand, bank count, and output — see product cards for current pricing.

What’s your return and shipping policy?

See our Returns & Exchanges and Shipping pages for eligibility and options.

Where can I see reviews and specs?

Open any product card to view detailed specs (amps, banks, chemistry modes, IP rating) and customer reviews.

How do I choose the right battery charger for marine use?

When selecting a marine battery charger, match the output to your battery type (flooded, AGM, Gel, or Lithium) and bank configuration. As a rule of thumb, the charger’s output should equal 10–20% of your battery’s amp-hour rating. For example, a 100Ah battery should use a 10–20 amp marine charger. Always choose chargers that are corrosion-resistant, ignition-protected, and compliant with marine safety standards.

Can I use a car battery charger on a boat battery?

It’s not recommended. A marine battery charger is designed to handle the demands of a marine environment and provides safer, more reliable charging.

Do I need a multi-bank marine charger?

Yes, if your boat has more than one battery (starter, house, or trolling motor). A multi-bank charger allows you to charge and maintain all batteries at the same time.

How long does it take to charge a marine battery?

Charging time depends on battery size and charger output. On average, a 10-amp charger will take 10–12 hours to recharge a 100Ah battery.

Why do you need a marine battery charger instead of a regular charger?

• Designed for marine environments: A marine battery charger is built to withstand moisture, vibration, and temperature fluctuations that destroy standard chargers.
• Protects your investment: Prevents battery sulfation, extends lifespan, and maintains consistent performance.
• Multi-bank charging: Many boat battery chargers can maintain multiple batteries at once - starter, house, and trolling motor banks.
• Smart charging technology: 3-step and 4-step charging profiles ensure safe, efficient charging without overcharging.

How do I install my Samlex Power 12-Volt 15-Amp battery charger?

The charger is required to be installed in a safe, well-ventilated, and dry location. Please see the details given under Section 1 - Safety Instructions. Mount the charger using 4 screws.

Each terminal consists of a tubular hole with a set screw. Insert the wire end in the tubular hole and tighten the set screw. The diameter of the tubular holes is as follows:

• SEC-1215UL 4 mm / 0.16 inches
• SEC-2415UL / SEC-1230UL 4.8 mm / 0.19 inches

To avoid polarity errors and possible damage, never use wires of only one color. Use Red insulated wire(s) for Positive connection(s) and Black for Negative connection(s) Recommended DC wire sizes are given below. The length in feet is the length of the pair of Positive and Negative DC wires from the charger to the battery / other DC load.

If the stranded wire is directly inserted in the tubular hole of the output terminal and the set screw is tightened, the strands will spread and the set screw may pinch only a few strands. This will result in loose connection, sparking, overheating, and voltage drop. For firm connection, crimp/solder Pin Type of Terminal has been provided for wire size for up to 6 ft:

• For SEC-1215UL / 2415UL: 4 pcs of PTNB5-13 (AWG #10)
• For SEC-1230UL: 4 pcs of PTNB10-12 (AWG #8)

How do I install my Xantrex True Charge 2?

Mount the Truecharge2 Battery Charger using all four mounting slots and holes which are provided. Mounting orientations a) and b) in Figure 5 meet IP-32 and drip-proof requirements that are needed to ensure safety in the presence of condensation. The other possible mounting orientations will not prevent the entry of dripping water and are not suitable for use in marine installations or other moist environments without the installation of additional drip protection. They are only acceptable for use in locations that are always dry.

To mount the Truecharge2 Battery Charger:

1. Select a mounting surface that is flat and allows for a minimum of 10cm (4 in.) of clearance on the top and bottom ends for airflow and at least 6 cm (2.5 in.) of clearance on either side.
2. Drill the four pilot holes for the mounting screws, taking care that there is nothing behind the surface that can be damaged by the drill.
3. Mount the Truecharge2 Battery Charger using corrosion-resistant, #6 (3 mm) round, pan head (or similar) screws. The top two keyhole-style mounting holes can be used to hold the Truecharge2 Battery Charger in place while fastening the bottom two screws. For secure, permanent mounting, use the holes in all four mounting flanges and fasten all four screws. Do not rely on screws only in the keyhole slots for the installation of the charger.

To make charger installation quick and easy, Xantrex recommends that the installation tasks be performed in the following sequence:

1. Mount the charger in position.
2. Connect the DC ground.
3. Install DC wiring including installing required disconnects, fuses, or breakers.
4. Install AC wiring including earth grounds.
5. Power up the charger.

The Truecharge2 Battery Charger must be connected to a grounded, metal, permanent wiring system, or an equipment-grounding conductor should be run with the circuit conductors and connected to the equipment-grounding lead on the charger. Connections to the battery charger must comply with all local and application-specific codes and ordinances. Xantrex recommends that you install a DC chassis ground (earth) wire from the ground stud on the Truecharge2 Battery Charger to the engine bus or DC ground bus. The DC chassis ground (earth) wire should be sized correctly with the power conductors, and both must be sized for the battery fuses that are used to protect the DC wiring. Refer to your local electrical codes to verify the requirements in your jurisdiction for your application.

To connect the DC chassis ground (earth):

1. Locate the ground stud on the Truecharge2 Battery Charger.
2. Connect the DC chassis ground (earth) from the ground stud to the ground bus. Use a flat washer, a lock washer, and a nut (included in the installation kit) to secure the connection.
3. Tighten the nuts to 2.3 N-m (20 lb-in.) torque and test that the wire is secure. Do not over-tighten as this may result in damage to the charger.
4. Install a DC circuit breaker or fused disconnect in each positive cable that is as close to the battery-positive terminal as possible. Consult your local electrical codes regarding the distance allowed between the battery and the fuse or breaker. For example, in most situations, ABYC standard E-11 requires no more than 7 inches (17.8 cm). Be sure the breaker or fused disconnect is open.
5. Route the wiring to the batteries and to the Truecharge2 Battery Charger. Avoid routing wiring through an electrical distribution panel, battery isolator, or other devices that will add voltage drops.

What makes the Mastervolt ChargeMaster 24V so unique?

Make the most of your batteries with the ChargeMaster series, plugging in and charging anywhere in the world. Mastervolt’s ChargeMaster guarantees fast and complete charging of your batteries no matter where you are. Thanks to Mastervolt’s innovative 3-step+ charging process, batteries also perform better and last longer.

All ChargeMasters can be easily connected to a MasterBus network with only one cable and one connection (with the exception of the ChargeMaster 12/10, ChargeMaster 12/15-2, and ChargeMaster 24/6). What’s more, you have the option for central, local, or remote monitoring, configuration, and control of your system.

Clear Display

A clearly lit display on the ChargeMaster provides all essential information: charge current, charge voltage, charge phase, and battery content measurement and/or battery condition measurement as a percentage of available Ah capacity. The display also provides an indication of MasterBus communication. Three buttons adjacent to the read-out panel allow for easy operation of the entire system.

The ChargeMaster is available in various models to guarantee you the ideal battery charger for any situation and demand.

Features

• For recreational and semi-professional use.
• Suitable for any type of battery, including Lithium Ion batteries.
• 3-Step+ charging technology for fast and complete charging, also charges depleted batteries.
• Memory function prevents overcharging in case of unreliable mains.
• Safe and complete charging due to standard safety features.
• Charging capacity up to 1000 Ah battery banks.
• Easy to connect and quick to install.
• Can charge multiple battery banks simultaneously.
• Built-in system functionality (MasterBus) in combination with other Mastervolt products.
• Clear control panel (with the exception of the ChargeMaster 12/10, ChargeMaster 12/15-2 and ChargeMaster 24/6).
• Supplies your system without battery.

Charging your batteries with every voltage

The Mastervolt ChargeMaster supplies a maximum capacity wherever you are via auto-ranging. Auto-ranging ensures perfect fully automatic operation anywhere in the world, regardless of the available mains voltage (90-265 V AC, 50 or 60 Hz). The 3-step+ charging technology guarantees fast and complete charging, while the cos phi 1-regulation gets the most out of limited generator capacity.

Robust Connections

Solid metal-to-metal connectors equipped with strain relief prevent corrosion and overheating.

Charging multiple battery banks

The ChargeMaster series has three equal charge outputs. Those of the smaller ChargeMaster models are pre-installed with two metres of cable for a plug & play solution, while the heavier models have one full output (for example for your service battery) and two outputs of 10 A, ideal for your starter batteries.

DC Power Supply

Even if the batteries are not connected, Mastervolt ChargeMaster battery chargers can provide a constant DC output allowing you to turn on lights or keep the fridge cold.

To ensure that your boat's battery stays functional and keeps your boat operating at peak performance, PartsVu offers a complete selection of marine battery chargers, inverters, converters, and isolators. Browse these essential electrical products from top brands, like Samlex America, ProMariner, Xantrex, Dual Pro, Minn Kota, Quick, and others.