With that in mind, it can be particularly frustrating when an RV’s batteries are depleted and need a charge before any of the camper’s appliances can be used.
What is one to do in this situation? What is the fastest way to charge RV batteries?
Many experienced RVers claim that the fastest way to charge RV batteries is by plugging the rig into shore power through a high-amperage smart charger. The smart charger allows the rig to charge at a high amperage, maximizing charge efficiency.
But that’s not the only way to charge an RV’s battery bank, nor is it the only step to proper RV battery maintenance. Regular maintenance of a camper’s battery bank is a simple way to protect a vital and expensive component of RV systems.
Four ways to charge RV batteries
Most campers have at least three, if not four methods that can be used to charge the battery bank. Each method of charging comes with a set of advantages and drawbacks. Forward-thinking RVers are knowledgeable on these methods and can accurately determine what charge method is best for any given scenario.
Four common ways to charge RV batteries:
- Shore power
- Power generator
- Solar power
- Alternator charging
Shore power
Deriving its name from days of maritime past, “shore power” for an RV refers to an external outlet that provides 120-volt alternating current (AC) power to a camper. Shore power outlets are supplied electricity from the main power grid and are found at almost all RV parks across the US.
Being connected to the grid, shore power supplies fast electricity that is virtually limitless. This allows an RV’s battery bank to charge quickly and efficiently. The only equipment needed to charge via shore power is a heavy-duty extension cord and, depending on the amperage of your RV, a power adapter.
Running the power through a high-amperage power charger, also known as a “smart charger”, increases the efficiency and speed at which an RV can charge. A smart battery charger can be purchased for anywhere from $50 to $200, depending on the quality and strength of the device.
Shore power pros
The primary advantage to charging an RV with shore power is the speed and efficiency with which the batteries can be charged. Additionally, shore power connections provide relatively clean and stable electricity that has low potential to damage appliances and equipment in the camper.
All RVs come standard with a shore power connection, meaning no expensive equipment or gear must be purchased to charge using shore power.
Shore power cons
Shore power comes with very few, if any drawbacks. The primary issue with using shore power to charge your RV batteries is that you have to pay for the electricity. This isn’t too bad when charging from your own house but can represent a significant fee at certain RV parks and campgrounds.
Power generator
Electrical power generators have been used to power and charge RV batteries for many decades. Generators are a safe and reliable way to create the energy needed to power an RV while camping far from city power grids.
Many large motorhomes have built-in generators that are installed by the maker at the time of manufacturing. These generators are typically wired into the RV’s primary electrical power system to simplify usability and have the ability to power all of the appliances in the motorhome.
On-board generators are also usually tapped into the main fuel tank of the rig, eliminating the need for manual refueling. Travel trailers rarely have built-in generators, but they can be found in large fifth-wheel trailers.
Travel trailers aren’t usually installed with built-in generators due to trailer weight restrictions. On board generators are simply too heavy. That leads most trailer owners to rely on a portable generator for their power needs.
Being relatively cheap, simple to use, and versatile, portable generators are a must-have item for any travel trailer owner.
Generator pros
A massive advantage to having a generator for a camper is that it opens up a whole world of boondocking possibilities. Who needs the grid when you can create usable electricity out of liquid fuel?
Generators can also act as a back-up power source if the power grid experiences a blackout, or your shore power connection fails.
Generator cons
Power generators are loud. Like, super loud.
In fact, generators are so loud that almost all RV parks have regulations that dictate exactly when a generator can be operated. These hours are typically between 7am and 10pm.
Beyond excessive noise, a drawback to using a generator for power is the need for fuel. Liquid fuel is heavy and expensive and can become a bit of a burden on long boondocking trips. Just make sure you always have an extra fuel reserve in case your generator drains your main fuel tank.
Solar power
Any RV that has solar panels has the ability to charge a battery using the limitless power of the sun. The size and wattage of a solar panel determines how much power it can generate and how quickly it happens.
Solar panels generate direct current (DC) power that can be directly transferred into an RV battery for storage and later use. A device called a charge controller is installed between the battery bank and the solar panel array. Charge controllers work to prevent power from trickling up the wire and discharging through the panels.
Solar power pros
An obvious advantage to using solar panels to charge an RV battery is that energy from the sun is absolutely free. Sure, you have to put up an initial investment to buy and install the panels and equipment, but after that you can harvest as much free energy as your batteries can hold.
Solar panels are silent and do not need to be turned on or off. As long as the sun is shining and all of the equipment is properly hooked up, your panels are generating power. Many boondockers love solar energy for this reason.
Eco-conscience RVers prefer using solar for all of their power needs, as it is one of the most environmentally friendly sources of power found on Earth. No liquid fuel or natural gas is burned by humans to generate solar power.
Solar power cons
While this might not always be the case, as of right now solar panels do not convert solar radiation into electricity quickly. Solar power systems can take a frustratingly long time to recharge a battery, making them a poor choice for quick charging of RV batteries.
An undeniable flaw in solar power systems is the unpredictable nature of weather patterns. If the sun is not shining, power is not being generated. This means that cloudy days, rain, and snow can all decrease or eliminate a system’s ability to produce electricity.
Accumulation of dust also has the potential to decrease the efficacy of a solar panel, leading to a need for frequent panel cleanings.
Alternator charging
An alternator is an electrical generator that converts mechanical energy into electrical energy. They are located in the engine compartment of a vehicle and keep the vehicle’s battery charged as the vehicle moves. Alternators can be found in cars, trucks, and motorhomes -pretty much any vehicle with a motor.
A motorhome’s alternator will charge an RV battery as the motorhome is being driven. Usually all it takes to charge is hopping in the driver’s seat and turning the ignition. Once the engine is running, power is being stored.
Pros to alternator charging
Keeping house batteries charged with an alternator is extremely easy. It happens while the vehicle is in motion whether you like it or not. This is especially beneficial during long road trips cross country. After a long day of driving, you know your batteries are good to go for the night.
Seeing as an alternator uses the mechanical energy produced by the engine to generate electricity, the same fuel that is being used for driving is also used to make energy. That’s a win-win situation, right?
Cons to alternator charging
Charging RV batteries with an alternator is only feasible if the vehicle is going to be driven for a few hours each day. Other than that, it’s not a super feasible campsite charging solution.
Once parked, most RVers do not want to move their rig until it is time to leave. This makes alternator charging impractical for the duration of most camping trips.
Travel trailer owners do not even have the option of alternator charging. Travel trailers do not have circuitry that enables the trailer batteries to charge using the tow vehicle’s alternator.
Tips for charging RV batteries safely
All batteries hold extreme power and extreme potential for danger. Caution and care must be practiced when charging and working on RV battery systems. These tips will help keep you and your crew safe while charging your batteries:
- Temperature: Never charge an RV battery that is 122°F or higher. Similarly, avoid letting RV batteries get colder than 32°F, and never charge them at that temperature. Doing so will weaken the battery and lead to premature failure.
- Battery charger: Make sure your battery charger is compatible with your RV’s battery type, amperage, and voltage.
- Moisture: Do not let your RV batteries get wet ever, especially while charging. Moisture is extremely dangerous to RV power systems and can cause ridiculous amounts of damage very quickly.
Two common types of RV batteries
As of 2023, two types of batteries dominate the RV market: Lithium and lead-acid. All types of RV battery are considered what is called a deep-cycle battery. Deep cycle batteries can be deeply discharged regularly without damaging or shortening their lifespans.
Lithium batteries
Lithium batteries are newer to the battery market than lead-acid batteries. They utilize lithium iron phosphate to store energy and are celebrated for their ability to be discharged to as low as 20% of their total power capacity without shortening their lifespan. This lengthens the amount of time between charges.
Lithium batteries have a greater energy-density than lead-acid batteries, meaning you get more energy storage per pound. They maintain a higher voltage while discharging and have a longer lifespan than all other types of RV battery.
Lead-acid batteries
Lead-acid batteries are a common form of rechargeable battery that is used in both automobiles and recreational vehicles. They utilize lead plates submerged in an electrolyte fluid to store electricity and power an RV. It is recommended that lead-acid batteries never be discharged more than 50% of their power capacity to preserve the lifespan of the battery.
As lithium batteries take a hold of the market, lead-acid batteries are being used in RVs less and less. Soon lithium batteries will be the primary RV battery type, leaving lead-acid batteries to the automobile industry.
RV battery maintenance
Follow these steps to ensure the health and longevity of your RV batteries:
- Trickle charge your RV batteries whenever the camper goes through a long period of disuse. A trickle charger maintains a small charge on a battery for a long period, preventing it from fully discharging and suffering damage.
- Clean battery terminal corrosion as it develops. Over time, unchecked corrosion will render the terminals of a battery useless, requiring the battery to be replaced.
- Over winter, keep batteries in a warm environment, never allowing them to lower to freezing temperatures.
Frequently asked questions
See what our readers want to know about charging their RV batteries.
What is a house battery?
An RV’s “house” battery is the battery used to power all RV appliances. The “auxiliary” battery lives with the engine and is used in the mechanical operation of a rig.
Do batteries store AC power?
Nope! RV batteries store DC power. DC power can be converted to AC power using an inverter, allowing it to be used by 120-volt AC appliances.
Conclusion
With the right gear, equipment, and a bit of knowledge, keeping an RV’s batteries charged isn’t too hard at all. Always use safe practices while interacting with RV battery banks and teach children to never touch them.
Happy camping!
