How To Makes a 48V Battery Bank the Best Option for a Solar Power System?

A 24V system can enable those with higher energy demands to run more powerful AC appliances, but most RVers can simply and affordably install a 12V solar panel and battery system that fulfills their basic DC and AC needs. Furthermore, electric heating and air conditioning can be operated more economically and efficiently by purchasing a 48V system with sufficient solar panels and battery storage!

When operating a significant load on a 12V system, more panels, bigger capacity charge controllers, massive battery banks, and an abundance of heavy-duty wire are required. Due to overall cost-space-benefit considerations, many solar users with larger energy demands are now switching from 12V to 24V or 48V systems.

By doubling the overall system voltage and lowering the amperage by 50% with each step increase in voltage, you may obtain the same wattage by using the simple equation Volts (V) x Amps (A) = Watts (W).

For instance, let's compute the amps (A) equation for a 1200W system:

1200W / 12V battery = 100A

1200W / 24V battery = 50A

1200W / 48V battery = 25A

The power (W) produced by each example is the same, but the amperage is decreased by raising the voltage. Because of the ensuing decrease in amperage, we can supply the same amount of power using smaller, less costly cables. This chart offers an excellent illustration.

This figure shows that a circuit in a “critical” state (voltage drop of less than 3%), with an electrical load of 100A for 15 feet (4.6 meters), requires a wire size of 2 AWG (35 metric). The circuit requires 6 AWG (16 Metric) wire at 50A over the same distance, and 8 AWG (10 Metric) wire at 25A will save you a good deal of money. The AWG scale may not always make sense to people who are unfamiliar with wire sizing. The wire gets smaller the higher the number and the cost per linear length decreases as the wire gets smaller.

It’s less likely that you’ll overload a wire and start a fire, burn out a fuse, trip a breaker, or harm an electrical appliance if you size your wires and fuses according to the amperage they can handle.

This illustration shows how higher voltage systems have fewer transmission losses, are lighter, more cost-effective, more efficient, and easier to construct.

To begin the planning process for any off-grid solar system, figure out how many total watt hours you use each day. This is your “Magic Number,” or the average daily power (in Watt Hours) that you will need for electrical appliances. Our Solar System Sizing Worksheet will take you step-by-step through the process. After determining your Magic Number, you may start sizing your system appropriately.

What is the Optimal Voltage for My Solar-Powered Device?

Here’s a decent guideline that engineers use to figure out what voltage configuration is ideal for your system based on cost, space, and benefit.

If the capacity of your solar array is:

When 12V is good, 1000W or less 1000W and less than 2000W, 24V is preferable. The Best is 2000W or higher than 48V.

Visit this blog to learn more about building a robust and safe 48V system.

Solutions for 48V Battery Banks with Series vs. Parallel Connections

Purchasing a 48V battery is the simplest method to begin using 48V. A ready-to-install 48V–50Ah Lithium Iron Phosphate (LFP) battery from Maxwolrd Power comes with a self-heating feature for any system. There’s a nasty pre-order offer going on right now for these bad boys, so you might want to move quickly! Each of these batteries can hold 1.92 kWh of energy at 80% depth of discharge (DoD). If linked in parallel (up to 8), the total capacity at the same DoD would be 15.3 kWh. Furthermore, if your battery bank is going to be exposed to lower temperatures, the self-heating feature is ideal. To ensure that the battery will charge effectively when the outside temperature dips below freezing, the battery uses a tiny bit of its energy to warm itself if the battery core temperature falls below 41°F (5°C) and the battery management system detects a charging current.

An additional choice is to establish a 48V battery bank by connecting four 12V batteries in series. Let’s examine the energy capacity that can be obtained by connecting lead acid batteries in series against lithium iron phosphate batteries in series. All lead acid batteries, including flooded, gel, and AGM models, have a safe depth of discharge (DoD) of 50% and a nominal voltage of 12V, for those unfamiliar with battery chemistry jargon. Higher nominal voltage ranges of 12.5–12.8V and a safe DoD of 80% are features of LiFePo4 (or LFP) batteries.

Now let's calculate.

Let’s link four 12V-200Ah batteries in series to make a 48V-200Ah battery bank using either 200Ah AGM or Gel batteries (both have lead acid chemistry). With a lead acid-safe DoD of 50%, this 512-pound battery bank can generate 4.8kWh (or 4800WH) of power.

Let’s now compare that to the chemistry of lithium-iron phosphate batteries. LFP batteries could only be linked in parallel until recently. Positive updates! The 200Ah-12V Lithium Iron Phosphate CORE battery from Maxwolrd Power is the company’s first CORE battery that can be connected in series! The overall battery bank capacity, at 80% DoD, is 8.2kWH (or 8200WH) when using a series setup with 4 x 200Ah CORE LFP batteries. It weighs slightly less than 190 lbs. Significantly different in weight and capacity compared to lead acid! This is a great choice for a whole off-grid home system or even a huge RV equipped with plenty of high-wattage domestic appliances.

Let’s take a closer look at the LYCAN 5000 Power Box, which comes with two of these potent Lithium Iron Phosphate (LiFePo) batteries, a 48V-3500W Solar Inverter Charger (which combines an inverter, battery charger, and charge controller into one unit), a BT-2 Module, and a Communication Hub for smartphone system monitoring. This will enable you to appreciate the 48V-50Ah battery’s power better from Maxwold Power. This robust all-in-one solar generator is made specifically to provide electricity in case of crises, during blackouts, or even for off-grid houses or recreational vehicles that are left parked for a season. The 48V LYCAN system’s 4.8kWh capacity and 3500W pure sine wave AC output (7000W peak power) are sufficient to power the majority of indoor and outdoor equipment. Its integrated design simplifies the process of setting up a large-scale, portable solar power system.

This unit has a 4.8kWh capacity, which is more than enough to run most heavy-duty indoor and outdoor appliances with a 3500W continuous power output and a remarkable 7000W peak power. It provides a 20A AC output for standard household appliances and a 30A AC output for larger or more powerful goods. If that isn’t enough energy for all of your demands, you can easily increase the LYCAN to 19.2kWh by adding up to 6 more 48V–50Ah Smart Lithium Iron Phosphate Batteries. This will cover almost any scenario, from brief blackouts to complete energy independence. It’s crucial to remember that no matter how much battery storage you install, your load capacity will remain at 3500W.

To evaluate the 20A output, we plugged in a variety of high-power household equipment, such as an electric heater, coffee maker, microwave, blow dryer, electric kettle, toaster, and instant pot. All of them worked well. We discovered that we could operate two higher-power appliances (like the coffee machine and toaster) simultaneously, but adding a third high-wattage appliance—like a hair dryer—tripped the breaker. As a result, the system performed as intended and as expected. Note: The total power consumption of the toaster, coffee machine, TV/laptop, and lights would be less than 20A (peak output) and 3500W (max load). Again, everything performed flawlessly! We even used the 20A output to drive big power tools like a compound miter saw, shop vacuum, and table saw! This unit would be an excellent source of power for a building project that is off the grid.

We tested the 30A output by using Hutch’s parents’ travel trailer’s 30A power cable to run the entire camper after carrying the gadget through the snow and ice. We ran any phantom power sources, such as the refrigerator, LP gas detector, and audio clock, while simultaneously testing their higher-wattage appliances, such as the microwave, heater, electric skillet, and coffee maker.

To prepare their camper for the upcoming camping season, we spent the majority of the day evaluating the device and organizing its contents. We used this time to run the heating, make coffee, and clean the handheld vacuum. To verify the peak power and circuit breaker performance, we utilized the 20A output to operate two more high-wattage appliances on the 30A and a blow dryer at 1500W. After running for 20 to 30 seconds, the breaker tripped. Since this would also overwhelm a campground’s 30A output, we were convinced that it could withstand a peak load before tripping the circuit breakers as planned. We even had 53% of the battery remaining at the end of the day. Amazing!

We think 48V systems are the way solar power will go in the future since more and more people are living off the grid but still want to be able to power their lives like they would in a typical home. Future sustainability is being ushered in by Maxwolrd Power battery products’ safety, efficiency, and cost-effectiveness.