Solar battery backup systems are becoming more popular as consumers are looking to bypass net metering, have power during an emergency, or are working towards having a Net Zero Energy Building. A NZEB is one that produces just as much energy as it uses so that it doesn’t pull power from the grid. While this may seem like a goal that is just out of reach, through advancements in solar battery composition and design, it is becoming more common and practical.
Integrated Battery Design
Traditionally, photovoltaic battery charging is done using two independent units connected by electric wires, meaning the battery is separate from the PV system. In reality, those types of systems are no longer the most practical or efficient way to store excess energy. They tend to be bulky, taking up extra space, and there is energy lost during the transfer from the system to the battery. An integrated solar battery system combines the energy generation and storage in one single unit, creating a more compact, energy-efficient solution.
There are three main designs for an integrative design, including direct integration, photoassisted integration, and redox flow battery integration.
- Direct Integration: This design requires stacking the battery and solar cell together so that they may function autonomously.
- Photoassisted Integration: Through the use of photocharging, the battery becomes partially charged.
- Redox Flow Integration: Photocharging is achieved through the use of a redox flow battery.
Versatile Battery Options
Lithium-ion batteries have historically been the most comm type used for solar battery backup systems. However, with new advancements in solar battery technology, it is no longer the only choice you have!
Aluminum-ion Batteries
New technologies are allowing researchers to develop solar batteries from readily available, inexpensive, and abundant Aluminum. These batteries have a high energy density, cycling ability, and coulombic efficiency.
Nickel-Zinc Batteries
These non-toxic, cost-effective, eco-friendly batteries are a good competitor when up against the Lithium-ion battery’s energy storage capacity. Unfortunately, their life-cycle is not as high as others, but ongoing research and development show high potential for commercial use in the near future.
Salt Water Batteries
Water has the ability to conduct ions for use in rechargeable batteries. Instead of requiring heavy metals, these batteries only need cheap industrial salt, manganese sulfate, water, and electrodes to create catalytic reactions. This reaction stores electrons as hydrogen for future use. Did we mention their components can be recycled? It’s a win-win. While this type of battery is not ready for commercial use yet, there is scalability potential on the horizon.
