Installing a new solar-powered system can appear confusing. There are so many types of solar panels, batteries, and other components — the amount of research needed to understand solar power can be daunting. Luckily, solar batteries are one of the more straightforward decisions you will have to make when installing a DIY solar system.
Generally, the two most popular options for solar powered systems today are Lead Acid and Lithium batteries. Lead Acid batteries can be flooded (higher maintenance at lower cost) or AGM (lower maintenance at higher cost). Taking a closer look at lithium batteries, the most popular lithium battery type is Lithium-Ion battery. Regarding Solar powered systems most used type is Lithium Iron Phosphate (LFP).
What Are Solar Batteries, and How Do They Work?
Without somewhere to send energy produced by your solar panels, solar would be fairly inefficient—your appliances would only work when the sun is shining and your panels are working. If you don’t use the energy, it’d be wasted—and you wouldn’t be able to use it at night. Enter solar batteries, which store energy generated by your panels for use when you actually need it. Solar batteries are an alternative (or addition to) feeding energy back to the grid and can help you make your house or facility somewhat immune from power outages and even help take it off-grid entirely.
Solar Battery Types
The four main types of batteries used in the world of solar power are lead-acid, lithium ion, nickel cadmium and flow batteries.
Lead-Acid
Lead-acid batteries have been in use for decades and are one of the most common types of battery used in automotive and industrial applications. They have a low energy density (meaning they cannot hold much energy per kg of weight), but remain both cost-effective and reliable and thus have become a common choice for use in a home solar setup.We recommend:best lithium batteries for golf carts
Lead-acid batteries come in both flooded and sealed varieties and can be classified as either shallow cycle or deep cycle depending on the intended function and safe depth of discharge (DOD). Recent technological advancements have improved the lifespan of these batteries and lead-acid continues to be a viable option for many homeowners.
Lithium-Ion
The technology behind lithium-ion batteries is much newer than that of other battery types. Lithium-ion batteries have a high energy density and offer a smaller, lighter and more efficient option. They allow the user to access more of the energy stored within the battery before needing to be recharged, making them great for use in laptops and phones—and in your home.
The major drawback of lithium-ion batteries is the significantly higher cost to the consumer. If improperly installed lithium-ion batteries also have the potential to catch fire due to an effect called thermal runaway.
Nickel-Cadmium
Nickel-cadmium batteries are rarely used in residential settings and are most popular in airline and industrial applications due to their high durability and unique ability to function at extreme temperatures. Nickel-cadmium batteries also require relatively low amounts of maintenance when compared to other battery types.
Unfortunately, cadmium is a highly toxic element that, if not disposed of properly, can have a significant negative impact on our environment.
Flow
Flow batteries depend on chemical reactions. Energy is reproduced by liquid-containing electrolytes flowing between two chambers within the battery. Though flow batteries offer high efficiency, with a depth of discharge of 100%, they have a low energy density, meaning the tanks containing the electrolyte liquid must be quite large in order to store a significant amount of energy. This size makes them a costly and impractical option for most household use. Flow batteries are much better suited to larger spaces and applications.
How to Choose the Right Type of Solar Battery for You
Lithium-ion and lead-acid batteries are the most popular options for residential and mobile solar systems. Here are the most important considerations when choosing a solar battery.
Size and Weight
Lead acid batteries weigh much more than lithium-ion ones. Plus, they require much more volume to store the same amount of energy. If you are building an RV or tiny home solar system, you will undoubtedly want to consider your space and weight limits.
Even if you plan on cramming the interior components of a residential solar system into a closet, you’ll want a compact setup. The smaller size of a lithium-ion battery system can benefit the homeowner in these cases.
Initial and Ongoing Costs
Lead-acid batteries have a lower purchase price but require replacement more often than lithium-ion and deliver far less efficiency. The replacement costs lead to a higher expense over the lifespan of a solar system. Lithium-ion is the better choice when considering costs unless you can’t afford the initial price.
Battery Capacity
Battery capacity can determine the type of battery to choose. If you’re only powering something small, you don’t require a large-capacity battery. In this case, a lead acid battery’s extra size and weight won’t be as much of a consideration.
In the case of a full-fledged solar system, you will need thousands of amp-hours worth of battery storage. Lithium-ion technology reduces the size and weight of a large-capacity battery system.
Ambient Temperature
The ambient temperature has a significant effect on battery operation. Lithium-ion batteries can receive a charge between 32°F (0°C) and 113°F (45°C). However, they can discharge at temperatures as low as -4°F (-20°C) and as high as 140°F (60°C). Lead acid batteries can charge and discharge between -4°F (-20°C) and 122°F (50°C).
You may need lead-acid batteries if you plan on charging in extremely cold temperatures. Alternatively, those using batteries in extreme heat should consider lithium-ion.
What is the best type of lithium battery?
LiFePO4 batteries are the safest of the lithium batteries, because they will not catch fire, and won’t even overheat. Even if you puncture the battery it will not catch fire. This is a massive upgrade over other lithium batteries, which can overheat and catch fire.
What are the disadvantages of lithium-ion batteries?
Despite its overall advantages, lithium-ion has its drawbacks. It is fragile and requires a protection circuit to maintain safe operation. Built into each pack, the protection circuit limits the peak voltage of each cell during charge and prevents the cell voltage from dropping too low on discharge.source:Flykol