Escapees May-June 2024

or off-gassing, as well as a longer lifespan, they are a decent investment over a fl ooded lead acid battery. They do have a higher internal resistance than AGM or LFP, leading to longer charging times. Lithium Iron Phosphate Battery (aka LFP or LiFePO4): This is a newer technol ogy for deep cycle batteries that differs from the Lithium Ion batteries commonly found in hand-held electronics. The LFP chemistry is much more stable, and virtually maintenance free. These batteries are not prone to overheating, and the internal computerized BMS (Battery Management System) provides protection against over/ under charging, reverse polarity and temperature challenges. Because they will not off-gas, the options for installation can include the living space of your RV, van, boat or off-grid home. With a decade or more of life expectancy and higher charging/ discharging rates, these batteries represent an upfront investment that pays off within just a few years—all of this at almost a third of the weight. Which Deep Cycle RV Battery is Best for My Rig, Energy Needs and Lifestyle? Once you have determined your average daily total watt hours using our Solar System Sizing Workshee t (See QR code for download ) and have determined how many batteries (amp hours) you need to meet your energy demands, it’s time to choose which deep cycle batteries are best for you. Here are some important considerations: Where will you mount your batteries and in what orientation? Lead acid batteries should be mounted outside on your tongue (or vented battery compartment) and must remain upright, while AGM, Gel and LFP can be safely installed inside your camper as they do not off-gas and can be oriented on their side. How much space do you have for your battery installation and is battery weight a factor in your situation? Each battery has slightly different dimensions and the weight of lead acid (50–64 lbs per 100Ah) vs LiFePO4 (23–27 lbs for 100Ah) is quite signi fi cant, especially if you are building a large battery bank.

Four Types of Deep Cycle Batteries When we started our solar powered journey in 2012, just about every off-grid RVer we met had installed two or more 6V golf cart batteries in series (around 60 pounds each!) and used a gas generator to recharge them. Well, times have changed! Today, deep cycle batteries offer signi fi cantly more capacity, weigh much less, charge faster and are overall safer to use. Deep cycle (12V–48V) batteries are designed to cycle from a full charge to a speci fi c safe depth of discharge and back to full charge hundreds to thousands of times, and can be charged and recharged in a variety of ways including solar panels, DC to DC chargers, AC to DC chargers, inverter chargers, converters, gas generators and more. The DC energy stored in these batteries can be used to directly power 12V appliances, as well as 120V appliances with the assistance of an inverter. It is important to note that deep cycle batteries are different from the average car battery—referred to as a CCA (Cold Cranking Amps) battery. A CCA battery is designed to deliver a lot of battery current (amps) quickly to get your car started and is not appropriate for an ef fi cient off-grid solar installation. Lead Acid Battery: These fl ooded (or wet) batteries were the industry standard for many years. While they remain the least expensive batteries, fl uid levels should be checked regularly, and should not be installed inside your living space due to potential off-gassing during charging. AGM Battery: Absorbent Glass Mat is a type of sealed lead acid battery which uses a fi berglass mat between the battery plates. This allows the electrolyte solution to exist in a “dry” or suspended state, rather than in a free, liquid form. AGM does not require any additional fl uid, off-gasses minimally and is maintenance free. With a wider charging temperature range, they can be a popular choice for folks living in colder climates. Gel Battery: Another type of sealed lead acid battery, uses a silica compound to thicken the electrolyte solution in the battery. They offer more fl exibility with installation options because they can be installed on their side. With no maintenance

Solar System Sizing Worksheet

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ESCAPEES Magazine May/June 2024