Posts

off-grid RV camping

Increasing Your RV Battery’s Capacity and Overall Runtime

/5 Comments/in /by

On Overlanding adventures where primitive campsites don’t have power hookups, your house battery may not be large enough to provide the power you need for the length of your stay.  On these occasions, one definitely does not want to run out of power for lights, cooking, or charging mobile devices. So if you’re venturing out into areas without power to plug into, it’s easy to add more battery power and run time if you have space.

Deep-Cycle Batteries and Amp-Hour Ratings

Many RVs come with a single 12-volt battery dedicated to the unit’s house power. To increase the capacity, you first need to make sure the battery is a deep-cycle model. Some RVs are outfitted with a typical automotive starter battery which works fine to provide lots of initial power to start an engine, but not for maintaining power over several hours for lights and other electrical accessories. Switching to one 12-volt deep-cycle battery is a start. It will provide power for a longer period of time, indicated in amp-hours (usually the 20 hour capacity in Ah).

Amp-hour ratings are shown on the battery label and will help you figure out how many discharge amps the battery can provide for however many hours you need to supply.  Here’s an example. The most common rating is the 20 hour capacity in Ah or rate in amps.  The capacity in amp-hours is found by multiplying the discharge time (20 hours) by the discharge rate.  The discharge rate is found by dividing the rated amp-hour capacity by the discharge time (20 hours).  For example, a battery that is rated at 100 amp-hours at the 20-hour rate would have a continuous discharge rate of 5 amps for 20 hours.  Similarly, a battery with a rating of 100 amp-hours at the 5-hour rate would have a continuous discharge rate of 20 amps for 5 hours, but its 20-hour capacity would be much higher than 100 amp-hours (probably closer to 130 Ah at C20).  When selecting a battery for a given application, it is important to use the rating that is closest to the average runtime needed between recharges in the application.  That, combined with knowing the total amperage your electrical accessories in your RV will draw, will help to determine how much battery capacity you will need.

Two-Batteries Are Better Than One

If you switched your house power to a deep-cycle battery with a greater amp-hour rating but find you still need more capacity, you can add another battery in parallel if you have space. Adding a second deep-cycle 12-volt 100 amp-hour battery connected in parallel, for example, will keep the voltage the same at 12 volts but will increase the capacity to 200 amp-hours.  This can double the discharge rate (10 amps for 20 hours) or simply run the system for a longer time between recharges.

If you have a large enough space in your RV to add more batteries, you can add a third 12 volt – 100 Ah battery connected in parallel.  However, it is not recommended to make more than three parallel connections.  If even more capacity is needed without increasing system voltage, another method is to connect 6-volt batteries in a series/parallel circuit.  Six-volt golf car deep-cycle batteries are designed with much higher capacity per battery. (200 – 250 Ah each).

Two six-volt batteries can be connected in series for 12 volts and then another set of two connected in parallel for 400-500 Ah or a third set in parallel for 600-750 Ah at 12 volts.

The difference in wiring batteries in series and parallel can be seen here. If you plan on attempting this upgrade, make sure to use high-quality large-gauge wiring and connectors, and talk to an RV electrician for any help in setting up a multi-battery bank system. Some systems like this need to be separate from the RV’s charging and electrical system. It will also require you to use a good-quality battery charger specifically for large capacity deep-cycle batteries. If Overlanding is a long-term lifestyle, many have also considered adding solar panels to the top of their RV to keep deep-cycle house batteries charged and provide consistent power when they need it.

While upgrading to more batteries is more expensive, the larger battery bank will lower your depth of discharge (DOD) on each battery to the recommended 50% or less. This will ultimately enable the pack to last much longer than constantly draining a single battery.

 

Four Wheel Campers - SLide-iN Camper

Pop-Up Camper Manufacturer Four Wheel Campers, Relies On U.S. Battery Products

/0 Comments/in , /by

With the surge of Overlanding at an all-time high, Four Wheel Campers has become the go-to brand for adventurers who travel beyond traditional camping locations. “Because many Four Wheel Campers customers venture to faraway places like Alaska, Baja, Central America, South America, and the remote southwest, they expect undeterred performance,” says Dan Welty, VP at Four Wheel Campers. “Their requirement for uninterruptable power over a longer period of time is essential. To meet this demand, we have selected U.S. Battery Manufacturing products as our sole supplier of AGM 12 and 6-volt batteries. Four Wheel Campers and our customers count on the performance and reliability U.S. Battery products provide. Having a national resource that warranties and services the occasional problem is required, and comforting insurance as well.”

The company was founded in 1972 and is the world’s leading producer of pop-up campers for trucks. The entire operation is located in Woodland, just outside of Sacramento, California, and over the years has become the go-to brand for those adventuring beyond traditional camping locations. The campers themselves fit into the bed of most full-size pickup trucks and feature a welded aluminum frame, one-piece aluminum roof, and aluminum siding. Wearable components like the collapsible pop-up material (typical 20-year life) can be replaced at the factory or dealer locations.

Four Wheel Campers can come equipped with one or two 12-volt or 6-volt U.S. Batteries. These batteries are recharged by the truck as it is Four Wheel Campers Interiordriving or by solar panels on the camper roof. “We have numerous customers living full-time with a combination of this power and occasionally plug into external (shore) power,” says Welty. “With two 6V batteries, our customers can run the refrigerator, numerous camper lights, and power smartphones for two days. With the 160 watts solar and, or truck driving, customers can be off-the-grid indefinitely.”

U.S. Battery AGM batteries are sealed and do not require watering. They feature low self-discharge rates, along with rigid-mounted and tightly packed battery cell plates to withstand shock and vibration found in motive power applications. These components work together to improve reliability, overall performance and deliver longer cycle life.

For more information on Four Wheel Camper products, visit https://fourwheelcampers.com.

overlanding house prowerrv

Increase Your RV’s House Power For Overlanding Adventures: Selecting The Right Battery

/0 Comments/in /by

Most RV’s are equipped with two types of batteries, one for engine starting and another that stores reserve energy to power appliances and the electrical systems in the RV (house power). Most campgrounds with RV parking have electrical hook-ups and when connected there’s no worry about draining your house power battery.  But as more RV owners venture to primitive sites, having the right kind of battery will keep you from running out of power during your stay.

It’s important to understand that there are different types of batteries that can be installed in RV’s for house power use. The most common is a standard 12-volt automotive starter battery. According to Fred Wehmeyer, Sr. VP of Engineering at U.S. Battery Manufacturing automotive starter batteries are not the best type to use for house power when primitive camping.  When you need reserve power to operate lights and appliances in your RV without electrical hook-ups, you need sustained power over a long period of time.  Automotive batteries are designed to provide very high current over a very short time to crank the engine, but are not designed to be discharged deeply and will drain quickly when powering the house load.  Also, the vehicle’s alternator/regulator charging system is not designed to fully charge batteries that are deeply discharged when used for house power.  This type of battery charging requires a dedicated charger that can be connected to AC power and also requires specially designed deep-cycle batteries to withstand the rigors of deep-cycling to provide many hours of reserve energy.

“Deep cycle batteries are a much better choice for RV house power.  They are available in both 6 volt and 12-volt sizes that can be connected in multiple series and parallel configurations to provide the amp-hour capacity at 12 or 24 volts, to support the runtime needed in the application,” says Wehmeyer. “Depending on the physical size and the internal design of the battery, battery manufacturers provide ratings on the battery label to indicate the runtime and amp-hour capacity at various discharge rates and times.  This allows the user to match the battery voltage and amp-hour capacity to the desired runtime for the specific requirements of the various loads (lights, appliances, etc.) and to select the best deep cycle battery type and configuration for the application.”

If you look at the types of batteries that owners of electric powered golf carts are using, the vast majority are equipped with 6, 8, or 12-volt deep-cycle lead-acid batteries because they provide reliable and cost-effective power over many years of deep-cycle service. “Switching your RV’s house power from an automotive starter battery to a deep cycle, RV/Marine or golf car-type battery will provide greater amp-hour capacity (reserve power) for Overlanding adventures and longer cycle life particularly when sized properly for a maximum of 50 percent depth of discharge (DOD) based on the battery pack’s total amp-hour capacity,” said Wehmeyer.

When discussing deep cycle batteries, there are essentially two types,  flooded lead-acid (FLA) and valve-regulated lead-acid (VRLA).  There are also two types of VRLA batteries,  absorbed glass mat (AGM) batteries and gelled electrolyte (GEL) batteries.  FLA batteries require regular maintenance such as checking the electrolyte levels and adding distilled water to the battery cells from time to time. This is to ensure the electrolyte completely covers the cell plates at all times, typically 1/4-inch below the bottom of the fill well of the cell cover.

Sealed VRLA batteries have no free electrolyte in them and do not require water addition.  In an AGM battery, the electrolyte is absorbed in a special glass mat separator, and in a GEL battery, the electrolyte is immobilized in a silica gel.  Both types of VRLA batteries require special chargers and/or charge algorithms to provide optimum performance and life.  They are usually heavier, more expensive, and do not last as long as premium FLA deep cycle batteries.

Deep-cycle lithium batteries are becoming more popular in many applications but Wehmeyer says that the chemistry of lithium batteries requires a battery management system (BMS) to safely control how the battery is charged and discharged.  While there are specialized chargers available for lithium batteries, it is not a simple proposition to safely add them to an RV’s electrical system.

As you can see, simply switching from standard automotive starting batteries to deep cycle batteries for your RV’s house power can be very beneficial.  Also, if later you find that you need additional runtime or capacity, you can add more batteries or switch to higher amp-hour capacity batteries.  Another option is to add solar panels and/or an auxiliary generator to be able to charge the batteries when AC power is not available.