Home Expansion Batteries: The Perfect Way to Improve Your Home Energy Backup

Do you feel that your existing solar energy system is no longer enough to accommodate the ever-increasing energy needs of your home? Or maybe you are just looking for an energy backup system to power your essentials during minor power outages.

In any case, a home expansion battery is the perfect solution for increasing the capacity of your home energy backup system and powering your home during power outages while also getting the energy backup companion for your off-grid adventures.

In this article, we will explain what a home expansion battery is, how do you power a house with a battery, and the benefits of using this home backup battery system.

What Is a Home Expansion Battery?

An expansion battery can essentially be thought of as a moderate to high-capacity battery pack fashioned into a compact and travel-friendly form factor. This battery backup for home is much similar to a portable solar power station or generator with the exception that an expansion battery is usually relatively smaller in capacity and physical dimensions.

As such, these systems are generally better suited to powering low-consumption appliances such as smartphones, laptops, desktop computers, TVs, etc. High-end systems, such as a Bluetti expansion battery, can offer you several hours’ worth of battery backup on their own, which is more than enough to get you through brief power outages or remote adventures such as camping.

However, this home battery backup system is best used to bump up the net energy capacity of your existing backup system, allowing you to enjoy an extended backup time. These systems come equipped with multiple outlets including a USB-A outlet, USB-C outlet, and a 12V DC outlet which can also double as a cigarette lighter.

Additionally, the high-end models of expansion batteries offer several recharging options, allowing you to recharge your energy back for home through a number of different power sources, including solar panels, AC outlets, lead-acid batteries, and through cars using the AC/cigarette lighter input port.

How Does an Expansion Battery Work?

Expansion batteries are similar to portable solar power stations and generators not only in construction, but also when it comes to functioning. These home energy back systems consist of three primary parts which include:

  • Battery
  • Charge Controller
  • Inverter

Let’s take a look into what each of these components do and why they are so vital for an expansion battery.


As the name suggests, an expansion battery is fundamentally just a battery with some added features and technology and so, it is only natural that these systems cannot function without a battery. The main function of the battery, as most of us are aware, is to store the energy produced by a power generation source so that it can be used at a later time when the need for it arises. As such, batteries are also responsible for discharging the energy.

Bearing this in mind, it is clear that expansion batteries need to be charged before they can supply you with energy, just like an ordinary battery. As previously mentioned, these energy backup systems have several input ports allowing you to charge them through different mediums such as solar, car, lead-acid batteries, and AC wall outlets.

However, make sure to use the correct port when recharging the system. For instance, when recharging it through solar or a lead-acid battery, connect the system through the DC input port for both of these energy sources to supply DC energy. Conversely, when charging through an AC wall outlet, connect the system through the AC port only.

Furthermore, there are several types of batteries that can be used in a home expansion battery. LiFePO4 batteries are preferred over other types because they offer you an improved charge and discharge efficiency, longer life term, and safety. In addition, these batteries are exceptionally lightweight compared to the alternatives and require no maintenance.

Bluetti expansion battery systems use only a high-quality lithium-ion (LiFePO4) battery that provides you with long and reliable backup even after a thousand charge cycles. As a matter of fact, the Bluetti B300 Expansion Battery employs a class-leading 3,072Wh (51.2V, 60Ah) LiFePO4 battery that can retain 80% of its original capacity even after 3,500 cycles.

Charge Controller

Although batteries have improved drastically over the years, offering you higher capacities, lifespan, and efficiency than ever before, these systems are still prone to problems such as overcharging and over-discharging. Both of these problems can accelerate the degradation rate of your battery, leading to a greater and faster loss of efficiency and lifespan.

In addition, when recharging your system, fluctuation in the input voltage and current can also damage the battery internals also leading to a loss of efficiency and lifespan. In order to protect the battery in your home expansion battery system from the aforementioned problems, these energy backup systems also come equipped with a charge controller along with a battery management system (BMS).

The charge controller and battery management system are battery regulators that manage and restrict the rate at which electric current is added to or drawn from your expansion battery in order to guard against overcharging, electrical overload, and possibly even overvoltage. Additionally, it regulates the discharges and keeps the battery from being drained completely, deep discharging, to preserve battery life.

This helps avoid situations that could shorten the lifespan or performance of the battery and could also lead to other detrimental hazards such as electrical fires.


It is imperative for any energy backup system to be able to provide you with AC energy output since most of the appliances we use, in our homes and elsewhere, run on AC electricity. This is where the inverter comes into play. The sole purpose of the inverter is to convert AC electricity into DC and vice versa.

For instance, consider a situation where you are charging your Bluetti expansion battery using an AC wall outlet. However, since the home energy backup system is essentially a battery at its core, it can only store DC energy, as batteries usually do. Therefore, the inverter is called into action; this electrical device converts the AC energy input from the wall outlet into DC before channeling it to the battery for storage.

Moreover, since batteries can only store DC electricity, they must also deliver only DC energy. Then how can they power the appliances in your home that only run on AC energy? This is, again, thanks to the inverter, which transforms the DC energy stored in the battery into AC before sending it out to the AC outlet port.

To summarize, the inverter functions to convert AC electricity to DC, and vice versa, allowing you to charge your system through an AC energy source and power AC appliances. Without an inverter, expansion batteries would only be able to support DC charging and power appliances that use DC electricity.

Using an Expansion Battery System: How Do You Power a House with a Battery?

Home Expansion Batteries

Powering your home appliances using expansion batteries is pretty straightforward and easy. The home expansion battery system comes with a traditional power button to turn on and off the system. To use it, simply plug in the device or appliance you want to power into the respective output port and press the power button once to turn on the system and voila, enjoy a reliable and lasting energy back!

We are all aware that you can use your home backup battery system during power outages to keep your essential items charged. However, one of the best yet underutilized uses of these systems is to reduce your monthly electric bill.

Intrigued? You should be! The way to do so is to stop powering your high-consumption appliances, such as coffee makers, using grid-supplied electricity and instead power them using your Bluetti expansion battery system. This reduces your overall consumption of grid-supplied energy and hence your electric bill.

The savings become even more prominent when you refrain from using grid electricity during peak hours, when the electricity cost is at its highest during the day, and instead use your backup energy system to cover your energy needs during that window.

Some expansion batteries, such as the Bluetti B300 or B230, also house LED indicators to represent the remaining charge in the battery so that you know when to charge the battery, when it’s full, and how much longer it will last before it needs to be recharged again.

As for recharging the system, there are multiple ways to do it as explained earlier. The best way to recharge the system, however, is to pair it with portable solar panels. This is because solar panels allow you to recharge your home backup battery system for absolutely free, using nothing but the natural light of the sun. This makes your entire battery backup system more cost-effective.

Additionally, solar recharging your system is something you can fall back on even during power outages since your solar panels will keep producing energy for as long as the sun is shining, unfortunately, the same cannot be said for other charging methods.

Benefits of Using a Home Expansion Battery System

Earn Savings

As we explained earlier, you can use expansion batteries to reduce your dependency on grid supplied energy and your monthly electric bill. Overtime, these savings can add up to quite a substantial amount and even allow you to recoup the cost of your system.

Peace of Mind

Since you can recharge your expansion battery for free using solar panels and reduce your consumption of grid-supplied power, you get to enjoy the peace of mind that any future surges in the cost of electricity will not affect you as much.


Expansion batteries, similar to solar power stations, produce completely emission free energy since they do not use fossil fuels. This means no toxic gases in your home helping you maintain a clean and safe environment.

Noiseless and Odorless

Batteries contain no moving parts and therefore, do not make any noise or release any unpleasant odors that would ruin the peace and quiet of your home.

No Maintenance

The advanced battery technology used in expansion batteries grants these systems an extended lifespan and without requiring any maintenance. This means you will be able to save a lot of money on maintenance and repair costs which you would have to pay with other energy back systems such as gas generators.

Key Takeaway

Battery Expansion units are the ideal home backup battery solution for keeping your essentials powered during power outages and off-grid excursions. These devices come in a compact and travel-friendly package, even more compact than solar power stations and generators, making them easy to place and store anywhere.

In addition, these energy backup systems can also be used to offset your inflated energy bills by reducing your dependency on grid-supplied energy. However, if your energy requirements are very demanding, then a high-capacity solar power station or generator would be better suited to your needs.  If you have any questions about the right product for you, contact our customer care team and we’ll be happy to guide you to what’ll best serve your needs.

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