The main part of an inverter is the battery. The battery section can be called as the heart of the inverter design. If it is not working, then the inverter is dead. Nowadays, there are different types of batteries for the inverter. So, we will have a look at the different variants of the battery that you can use for the inverter. Each of these batteries has got its own pros and cons.
Let us get started.
1. Lithium ion Battery
Lithium ion battery is currently the most preferred battery for using in inverters. So, lithium ion batteries have become very popular now. There are multiple reasons for this popularity. It includes the long lifespan of the battery, the high energy density factor that allows going for a smaller size compact battery, and the ability to charge fast. When you look at the other popular lead acid battery, they are bulky and heavy.
The operation of a lithium battery is quite simple. The movement of ions between the cathode and the anode is responsible for supplying the current to the load in the case of the lithium ion battery.
Even though the basic cell chemistry of lithium batteries are same, there will be minor variations in the different types of lithium ion batteries available in the market. The cost will also vary for each of these types. You can get lithium ion batteries with lithium iron phosphate, lithium manganese oxide, and lithium cobalt oxide. Among these, most inverter manufacturers prefer to go with lithium iron phosphate batteries. There are multiple reasons for this choice. One is the excellent performance of the lithium phosphate battery in hot climatic conditions. Other two factors include the safety aspects and the cycle lifetime.
Lithium ion batteries used in inverters do come in different variations too. They are given below.
1.1 Lithium ion Powerwall Batteries
A lithium ion powerwall battery stores energy with the help of solar power. If there is a power cut, these batteries will deliver the power to run the various appliances. They are typically used in homes. The electronics integrated with the lithium ion powerwall battery are capable of detecting power cuts and automatically switching on to the battery source as the power.
These batteries are connected to solar panels. These solar panels convert sunlight into electricity. So, they store the excess energy during the daytime. This stored energy can be used later during the night. These lithium ion powerwall batteries are similar to the electric car lithium ion batteries and smartphone batteries. But they are much larger in size. Each of these powerwall batteries will have a lot of lithium ion cells inside it. All these cells will be connected in series and parallel arrangements. It is done to get the required amount of voltage and power rating. The casing for the powerwall batteries is extremely
durable. They can withstand any weather conditions. These lithium ion batteries can also get charged through the grid. So, even if the solar energy is insufficient, the batteries can get store the remaining power from the main grid also.
The importance of lithium ion powerwall batteries is increasing day by day. It is due to the fact that the entire world is looking for a sustainable and renewable form of energy. Thus, it can help to reduce the dependence on fossil fuels. The compact size of the lithium ion powerwall batteries also ensures that they are easy to install. You can get lots of space saving if you opt for this type of battery. The maintenance is also very less for the powerwall batteries. Thus, lithium ion powerwall batteries will be a cost-effective solution.
1.2 Lithium ion Server rack Batteries
A popular lithium ion battery category is the server rack lithium ion battery. They are popular because of their use in data centres. Data centres need to be up and running 24/7. This continuous working of the data centre demands a high performance and efficient battery. It is why they prefer lithium ion server rack batteries. There are many advantages for the lithium ion server rack battery that makes it the primary choice for data centres. Among that, one main advantage is their cost effectiveness. Reliability and efficiency are the other two factors.
If you compare it with lead acid batteries, they are highly efficient. The high energy density feature of the lithium ion server rack batteries makes it possible to store more energy inside the battery. Thus, the battery will occupy very less space when compared to lead acid batteries. If you check the charge discharge efficiency of the lithium ion server rack battery, they are quite high. It ensures that the battery can supply constant energy to the load for more periods of time. The amount of energy wasted will be very low if you use these batteries in the data centres.
If you compare the reliability of lead acid batteries with the lithium ion server rack battery, it is quite high for the lithium ones. The cell chemistry of the lithium ion server rack batteries ensures that they are less susceptible to failures. Stability is high for lithium ion batteries. Also, you can use these batteries in different climatic conditions. Temperature changes are not going to affect the performance of the lithium ion server rack batteries. When you take the safety aspects, the chances of the lithium ion server rack battery exploding is very less when compared to the lead acid ones.
If you take the cost factor, you may find it more expensive than the lead acid ones. But when you consider the other advantages, the return is better for the lithium ones. If you are looking for a long term solution for your data centre, a lithium ion server rack battery will be the best choice. You can also recycle these batteries. Thus, they are environmentally friendly too.
1.3 Lithium ion Stackable Batteries
Lithium ion stackable batteries are a complete breakthrough when it comes to power storage. The main feature of these stackable batteries is that you can increase the energy storage capacity according to your needs. It means if you are using lithium ion stackable batteries and you need more power, you can easily add more lithium ion batteries to the existing stack. Thus, this type of lithium battery brings up the upgradability feature to your battery without dismantling the existing one.
Here, there will be multiple lithium ion battery blocks that the user can connect in parallel and series arrangements to meet the energy storage requirements. There will be an intelligent battery management system connected to this network of stackable lithium ion batteries. This system will ensure that all the stacked batteries in the network get charged properly. This modular feature of the lithium ion stackable batteries makes it a preferred choice of battery in the big scale energy storage applications. So, the bigger inverters that require the scalability feature can go for the lithium ion stackable batteries.
Most applications will make use of solar panels to charge these batteries. So, when the battery capacity gets increased, you need to increase the number of solar panels also. It ensures that there is no drop in charging times for the battery. Also, you can scale down the batteries if the demand is less. The higher energy density of the lithium ion stackable batteries ensures that they don’t take up much space. So, it is an ideal energy solution for small spaces. It is also quite easy to install these batteries since they are available in modular form. The maintenance is also less for the lithium ion stackable batteries. You can make your energy solution environment friendly and green if you go for the lithium ion stackable batteries.
2. Lead Acid Battery
In early days, the lead acid batteries were used in most of the inverter designs. There are two main reasons why they are commonly used in inverters. The first reason is their popularity. The second reason is their cost. They are pretty inexpensive to use. These batteries will have lead dioxide and lead inside. Sulfuric acid is the electrolyte in this type of battery. You need to connect a load to the lead acid battery. This will initiate a chemical reaction inside the battery. The electric current is produced through this chemical process. This current will be passed on to the connected load.
There are 2 types of lead acid batteries. They are the sealed lead acid battery and the flooded lead acid battery. The pros and cons will vary for each of these batteries. If you are going with the flooded type battery, you need to do maintenance on a regular basis. There are multiple steps involved in the maintenance. It includes regular inspection and electrolyte filling. If you want to avoid this kind of maintenance activity completely, go for the sealed batteries. You can completely avoid the electrolyte filling part if you go for this one.
3. Nickel Cadmium Battery
Earlier, inverters used Nickel cadmium batteries for storing energy. They are also called NiCad batteries. There were two reasons for this popularity. Firstly, the NiCad batteries came with high energy density. Secondly, the life cycle of the NiCad battery is long. But later, the NiCad batteries got replaced by other types of batteries. The two main reasons for this replacement are the toxicity of the battery and the price. Cost is a major concern for most of the inverter designs.
The movement of nickel ions between the anode and cathode in the battery creates energy. Once the load is connected to the battery, there will be current flowing out of the battery.
4. Nickel Metal Hydride Battery
Another type of battery that is popularly used in inverters is the Nickel Metal Hydride battery. They are also called NiMH batteries. When you compare the Nickel metal hydride battery with the Nickel Cadmium battery, the toxicity level is high for the NiCad battery. Thus, the NiMH battery is more environmentally friendly.
The basic working of NiMH batteries is quite simple. Here, there will be movement of metal hydride ions between the anode and cathode. This movement of metal hydride ions is responsible for the production of current in the battery. This current gets transferred to the load connected to the battery. You can get NiMH batteries in different capacities and power ratings. The NiMH batteries are commonly seen inside the pure sine wave inverters. They are also used inside the modified sine wave inverters.
The life cycle of the NiMH battery is less. When you compare it with the lithium ion battery, the energy density is high. These two factors make this battery now a less popular choice for inverters. Nickel Metal Hydride batteries are expensive when compared with lead acid battery.
5. Flow Batteries
Nowadays, we are also seeing the emergence of a new type of battery in the market. They are called flow batteries. They come in very high capacities. It is one of the main reason why they are being used in high capacity inverters.
The working principle of the flow battery is completely different. Here, there will be two electrolytes. There will be separate storage compartments inside the battery to store these two electrolytes. There will be a membrane between these two tanks. The electrolytes will get pumped through this membrane. This movement results in the formation of an electric current.
Another thing about the flow battery is that you can get it in different chemistries. Zinc bromine and Vanadium redox are the two popular variants of flow batteries that are currently used in the market. One main advantage of the flow battery is its long life cycle. If you want a long term battery option, the flow battery is a good choice. But one main disadvantage of the flow battery is its price. They are quite expensive. It is due to the fact that they are pretty new to the market. So, when you use the flow battery in an inverter, it can increase the overall cost of the inverter. If the cost is not a constraint, you can always go with the flow battery.
Now you know you can use multiple types of batteries in an inverter. Even though lead acid batteries are quite popular when it comes to inverters, lithium ion batteries are slowly replacing them. All these batteries have got its advantages and disadvantages. So, you need to select accordingly. The selection of battery will fully depend on your design requirements. NiCad, NiMH, and Flow batteries are also good choices if they can meet the design requirements of the inverter design.