All marine batteries will need to be recharged while in service. Most boats with inboard engines and many with outboards will generate electricity for battery charging while the engine is operating. When it is not possible to run the engine many other options exist for recharging your batteries. Listed below are the primary marine electrical recharging equipment categories.
Portable Battery Chargers
Marine portable battery chargers or maintainers are designed to both recharge your batteries, and extend your battery's service life. This class of chargers are ideal for applications where the battery is stored for extended periods of time. Unlike automotive "trickle" chargers, marine portable chargers will not boil off the electrolytes in lead-acid batteries. Small battery chargers are lower in cost, smaller in size, making them a convenient alternative to larger fixed-mount types. Portable chargers are useful for recharging batteries that power trolling motors, personal water craft, and other small water craft. Most small battery chargers feature LEDs that let you know that the unit is recharging and maintaining your batteries. Typically, these units will have a short AC cord (6 ft.) and DC alligator clips for attaching to the battery terminals. These chargers are not generally supported by shore power systems.
EXAMPLES: GUEST offers several models (BatteryPal, etc.)
Battery Chargers (fixed mount)
Dedicated marine battery chargers are available in wide range of sizes, complexity, sophistication and cost. Battery chargers are available in configurations designed to charge single, dual or multiple battery systems. These chargers are designed for a fixed mount installation to a bulkhead or other suitable surface. Additionally, battery chargers in this class are typically hard-wired into the electrical system and are supported by an appropriate shore power AC input.
EXAMPLES: Charles; GUEST; Promariner; Victron; Xantrex
Voltage Inverters (AKA Power Inverters)
A voltage inverter transforms the DC electricity stored in batteries into standard household AC power when shore power is not an option. Voltage inverters are available in portable and fixed-mount models.
Portable Voltage Inverters typically connect to the DC electrical system through a cigarette lighter socket style outlet. The inverters in this class are designed to provide a smaller AC output suitable for powering laptop computers, small appliances, portable TVs, cell phones, etc. AC output: 400 watts or less.
Fixed-Mount Voltage Inverters (AKA Permanent-Mount) are efficient and reliable devices that come in a variety of sizes and power ranges to satisfy nearly any power requirement. These larger voltage inverters typically produce AC power in one of two types. The first type, MSW or Modified Sine Wave inverters work reliably for many of the commonly available AC appliances. The second type, TSW or True Sine Wave inverters are a better choice when delicate electronics are powered, this would include computers, plasma screens, stereos and home theater audio systems.
Voltage Inverter/Chargers (AKA Power Inverter/Chargers)
An inverter/charger is a combination of an voltage inverter, DC battery charger and transfer switch built into one system. When AC power is supplied, an inverter/charger recharges the house DC batteries. The inverter/charger permits extra AC power to power downstream smaller AC loads, like a portable radio, television or compact kitchen appliances. When AC power is disconnected from the inverter/charger, the unit inverts DC battery power into AC electricity.
Marine battery isolators direct the charging output from one alternator to two or more batteries without connecting them together. In operation, a house battery may be discharged without also discharging the starter battery. An isolator provides for both batteries being charged automatically and independently whenever the engine is running. The battery isolator is a simple solution to a serious problem. Many battery isolators now include a compensation diode that slightly increases the output voltage of the alternator to compensate for any voltage drop across the diodes.
Battery Monitors (AKA Power Accessories)
A battery monitor calculates ampere-hours consumed and the state of charge for a battery or multiple batteries. Ampere-hours consumed are computed by measuring the current flowing in or out of the battery. A typical battery monitor displays voltage, charge and discharge current, consumed ampere-hours and remaining battery capacity. Advanced battery monitors feature an internal alarm relay, that will run a generator when needed or will turn off devices when the battery voltage exceeds programmed settings. A battery monitor supplies important information about the status of your battery bank and making it as easy to read as a fuel gauge.
A solar battery charger transforms sunlight into electricity stored in DC batteries. Solar chargers are available in several styles and configurations making them a viable alternative to other charging systems. Solar power is clean, silent (no moving parts), reliable, green, and safe.
Foldable Solar Chargers
PowerFilm Foldable Solar Chargers are designed for users who need a lightweight and portable power source for recharging laptop, cell and satellite phones, GPS units and more. PowerFilm chargers can be combined with a variety of accessories to make it useful for many applications. These foldable solar chargers are very compact and lightweight. They can easily be carried and stored in a backpack, laptop bag or even a large coat pocket. These folding chargers are built to durable, UV and weather resistant, making them ideal for outdoor use. They range in size from 5W to 60W.
Rollable Solar Chargers
PowerFilm rollable solar panels (thin film on plastic) are truly a more flexible alternative to rigid solar charging solutions. PowerFilm rollable panels feature a lightweight, rugged, flexible construction that is perfect for a wide variety of locations and outdoor applications. These panels may be affixed temporarily or permanently with several mounting options. The rollable characteristic makes these panels very easy to stow away when not in use. PowerFilm panels range in capacity from 7W to 28W.
Marine Grade Fixed Solar Panels
GANZ Eco-Energy designs solar panels that provide clean, quiet and reliable power for many outdoor applications. The Ganz panels are fully weatherproof making them ideal for use in the marine environment. These panels feature a break resistant plastic film surface with a semi-flexible aluminum backing plate. These panels are designed to be mounted on a flat surface or and conform to a gently curved deck. Each panel has four rugged mounting grommets and 10 feet of outdoor rated power cable to connect directly to your battery or a charge controller. Ganz solar modules are an excellent source for slow charging 12V DC batteries and other electrical devices.
Boatowner's Mechanical and Electrical Manual 3rd Edition, by Nigel Calder, is an excellent resource and an essential troubleshooting guide for any boater, from the extreme novice to seasoned veteran. If it is on a boat and has screws, wires, or moving parts, it is covered in the Boatowner's Mechanical and Electrical Manual. Nigel Calder provides comprehensive advice on: battery technologies, 12 and 24 volt DC systems, corrosion, bonding & lightning protection, generators, inverters, battery chargers, electric motors, electric lights, marine electronics, antennas, RFI, diesel engines, transmissions, shaft brakes, and propellers.
The Electrics Companion, by Pat Manley, will help you figure out how much energy you are consuming and how much each item uses per day. Most of the equipment we 'switch on' consumes electricity, even the panel lights and voltmeter all add up. Author Pat Manley's guide will help you understand your battery capacity and charging requirements.
Simple Boat Electrics, by John Myatt, contains all the information needed to troubleshoot 12-volt electrical systems. It explains how to locate a fault, correct the problem when you can, or adopt a "get-you-home" solution if you can't. Provides some basic theory so you can understand what you're doing with a special emphasis of seamanlike practice of anticipating and preventing trouble.
The Arco Electrical Technical Manual, is packed with information to help you become more proficient in servicing sophisticated marine electrical systems. The Arco Electrical Technical Manual explains the fundamentals of troubleshooting electrical systems. Written in easy to read style with lots of illustrations and examples. Written by mechanics for mechanics.
The 12 Volts Made Easy - DVD<, is a nuts and bolts 12 volt electrical systems primer that is presented in a clear and easy manner. Subjects covered include: basic electrical theory, circuits, battery maintenance, basic wiring diagrams, controls, transducers, recharging, marine components, lights, motors, troubleshooting, basic repairs, installations, and more. Running Time: 60 minutes.
The 12 Volt Sailor - DVD, will help you to learn how to design and build an efficient electrical system for any vessel. This program illustrates how to integrate the radar, watermakers, windlasses, single side band radios, auto pilots, and GPS devices into any D.C. System. Running Time: 45 minutes.