How To Choose the Right Solar Battery For You
So, you’ve decided to invest in a solar system for power. That’s fantastic! Solar systems are an excellent way to help reduce your carbon footprint and contribute to the fight against climate change. A good system can take care of almost all of your energy needs. Plus, some energy utilities may even pay you for any excess energy your solar system adds to their network
Of course, your solar system needs more than just a few panels on the roof if you want it to work.
Solar batteries are critical for any good solar system. Without at least one solar power battery, your system will have no way to store energy, which means your solar panels would be a little more than expensive decoration.
When it comes to such important equipment, it’s essential to make sure you’ve got a high-quality battery that’s designed to handle your power needs. That means you need to know what kinds of solar batteries are available and which batteries will best be able to handle your needs.
Choosing a battery is no small task. Don’t worry though, we’ll cover everything you need to know to choose a great battery (or batteries), and we’ll cover some of the details that will help you customize your solar battery bank to your unique needs.
We’ll also talk about the long-term potential of your batteries, when you should expect to need replacements, along with other important details. That way, you’re prepared for everything your new solar system throws at you and can anticipate the costs of your solar along with the benefits.
Let’s get started!
Contents
Why Choosing the Right Solar Storage Battery Matters
Your solar power battery is the main reservoir for the energy your solar panels produce. That means it’s the battery that actually feeds your home energy system. Your solar battery pack also stores energy long term, providing power overnight and anytime your solar panels aren’t actively producing energy.
That means your home depends on your solar batteries during storms, electrical utility outages, and even when it’s too cloudy for solar energy production.
Having a good battery can make the difference between not producing enough energy to meet your needs and being able to produce and store a surplus of that energy.
High-quality solar batteries also tend to last longer and store more energy than cheaper, less-efficient models. That means your long-term costs for storage and battery replacement are significantly lower when you purchase a more efficient model.
Of course, no one battery is perfect for every user. Matching your needs and budget to the right battery will give you better results than just buying the best available option blindly.
Here’s what you need to know.
The Types of Solar Batteries
There are several options for different kinds of batteries for your solar system. Each option has its own pros and cons and operates slightly differently. Choosing the right type of battery for your needs is probably the most important part of choosing the right battery for your home.
Remember that you’ll also need a solar battery charger to operate your solar battery storage and solar system. That’s because there’s some power conversion that needs to happen before the energy can be safely stored in a battery. Your solar power battery charger should be included with professional solar power installation, but you’ll need to make sure you have one if you’re installing it yourself.
Lithium-Ion Batteries
Lithium-ion batteries are familiar to most users these days since this technology is now the single, most common battery type across all applications. That’s because lithium-ion batteries offer incredible efficiency and longevity. Lithium-ion batteries are a good choice from an efficiency and environmental perspective since they can hold more energy and last longer than other types of batteries.
In addition to holding more power on average, lithium-ion batteries also have a higher cycling limit than most alternatives. A battery cycle represents that battery being fully charged and fully drained one time. The more cycles a battery has before it can no longer take or hold a charge, the longer life that battery will have.
However, for all their benefits, lithium-ion batteries do have one big downside – cost. Lithium-ion batteries tend to be more expensive to manufacture than the alternatives. Those costs get passed down to the consumer, which means that lithium-ion batteries tend to cost more upfront even though they cost less than other batteries in the long run.
Sealed Lead-Acid Batteries
Sealed lead-acid solar-powered battery packs are a good option if you’re looking for a low-maintenance battery but don’t want a higher-cost lithium-ion battery. These use the same technology as flooded lead-acid batteries (which we’ll talk about in a moment) but are completely sealed and spill-proof.
Because these batteries are sealed and spill-proof, they are a good option for homes where you don’t want a lot of maintenance, as well as secondary homes you only occupy part of the year. This battery type is also popular with cabin owners and vacation property owners who are away from their residence for long periods.
Another advantage of this system is that the batteries will not self-discharge because it’s been a long time since they were used. That means your batteries should always have power but can also shorten their life span slightly.
Flooded Lead-Acid Batteries
Flooded lead-acid batteries don’t rely on recent technological advances like lithium-ion batteries do. In fact, this style of battery existed before the twentieth century and has been in continuous use almost its whole history.
The main advantage of this battery style is that it is simple, easy to use, and easy to dispose of once they’re dead.
However, these batteries have a couple of important downsides. For one thing, unlike sealed lead-acid batteries, these need a fair amount of maintenance. The batteries can’t work unless the cells are completely underwater, which means you’ll need to add more water every few months. The batteries also produce toxic fumes, so they need to be stored in a protected but well-ventilated area.
That said, if you’re looking for a low-cost and reliable solar panel battery system, this kind of battery might be a good match for you.
AGM Batteries
AGM batteries are another kind of lead-acid battery, but instead of using liquids like regular lead-acid batteries or sealed lead-acid batteries, these use fiberglass to transfer electrons between battery plates. Using fiberglass instead of liquids allows the battery to operate “dry,” making them a safer option for solar-powered RVs. This type of battery is also common for charging personal electronics from solar systems or small solar panels.
Gel Batteries
We don’t particularly recommend using gel batteries. There are just too many disadvantages to this style. However, since they are still relatively common for solar systems, we wanted to cover them.
The main advantage of this style of battery is that the electrolyte solution is slightly thickened, explaining the name, which makes them a little more durable. The thickened solution is also less likely to leak and won’t leak as much if the battery is damaged.
The problem is that this battery has a very narrow bandwidth where it can charge effectively. If the energy input is higher or lower than that bandwidth, it can damage the battery, shortening its effective life span.
Gel solar batteries also tend to be relatively expensive, so there isn’t a cost advantage compared with longer-lasting alternatives.
How Long Do Solar Batteries Last?
The short answer is that most solar power battery banks will last between 5 and 20 years, with most batteries falling in the 5–15 range. However, the exact life of your batteries depends on several factors that can make it relatively hard to predict. Here are some examples:
- Battery temperature (both in use and resting)
- Overall usage
- Whether you have overcharge protections
- Maintenance (how often it needs maintenance and how well maintenance schedules are followed)
Your battery’s temperature is critical for its life span. Ideally, the battery should be in an insulated area where the temperature won’t fluctuate too often but with enough breathing space to help prevent the battery from getting too hot.
The more you use your battery, the shorter its lifespan – simple as that.
Overcharge protections help stop your system from pouring energy into a saturated battery. They help preserve the battery cells themselves and can also help keep your battery from getting too warm.
How Many Batteries Do You Need?
There are a few things you need to think about in terms of how many batteries you need. First, you’ll need to know roughly how much energy you and your family use. You can likely get a monthly estimate from your current electrical company.
At minimum, you’ll need a battery or batteries that can support that level of energy use along with a solar panel capable of charging those batteries slightly faster than the energy is being drawn from them. More batteries won’t help if your solar panels aren’t producing enough power in the first place.
You also need to know how battery power storage is measured and how to convert it into a more useful measurement for your needs. Battery storage is measured in Ah (amp hours) and the rate it can transfer that energy is measured in Volts (V). However, your energy use is best measured in Watt-Hours or Wh. To get the Wh your battery contains, you’ll need to multiply its Ah by its V. So a 100 Ah 12V battery offers 1,200 Wh.
If your home needs 1,200 watts an hour, that battery provides about 1 hour of power. If your home only uses 60 watts an hour, then the same battery would provide about 20 hours of use.
That should give you the information you need to estimate how long each battery will last in your home. From there, you can estimate how much time you’ll need to run off battery power (remembering that your solar panels don’t provide power overnight or on heavily overcast days) and use that to calculate your battery needs.
How To Choose The Right Solar Battery
The right solar panel battery needs a few things:
- It must be compatible with your battery system.
- It must store a reasonable amount of power either on its own or in a power bank with other batteries.
- It must be compatible with any other batteries in the system.
- It must meet your maintenance requirements.
- You must have space to safely store a battery of its type.
- It must be within your budget (planning on replacement within 5–15 years).
If you aren’t comfortable determining what battery best meets those criteria, you can always hire an electrician to figure out the best options. An electrician can also handle battery installation if you aren’t comfortable installing your new batteries yourself.
We tend to recommend lithium-ion batteries because of their longevity and efficiency, but the other types can also be a good option for some users.
Our Top 3 Picks
If you’re looking for a quick list of the best solar batteries to choose from, you’re in the right place. Here’s our quick list of the batteries we recommend and why we think these are great picks.
1. Renogy Li 12V 100Ah Smart Lithium Iron Phosphate Battery
- 【Upgraded BMS Circuit】 Equipped with seven pairs of Mosfet and two pairs of XT90 are designed to allow a peak current of 150A to pass through, providing emergency charging and discharging option...
- 【Uncompromising Quality】 The high-quality pouch cells surpass severe high temperature and puncture tests to avoid fire or explosion. This battery has also passed international standards and...
- 【Activation Switch】 With the activation switch cable, you can turn on or off multiple batteries in parallel to ensure the safety of installation and use. The open-circuit voltage is extremely low...
This 12V lithium-ion battery offers some of the best performances on the market. It’s rated for up to 4,000 cycles, ensuring that it should last through years of regular use. Overcharge protection also helps prevent premature damage to the battery, also improving the battery’s life span.
A universal fit type helps make installing this battery significantly easier. Plus, this battery’s wide operation temperature range means it’s suitable for most installation locations and climates.
2. Universal Power Group 12V 100Ah Solar Wind AGM SLA DEEP Cycle VRLA Battery 12V 24V 48V
- UB121000 SLA is a 12V 100AH Group 30H Sealed Lead Acid (SLA) Maintenance Free Rechargeable Battery, UL Listed
- The spill-proof SLA/AGM battery features high discharge rate, wide operating temperatures, long life and deep discharge recovery.
- Rechargeable battery that can be mounted in any position, resists shock and vibration. Long lasting high performance in high and low temperatures.
If you’re looking for an efficient sealed lead-acid battery, this is a great option. Its durable design is meant to last while providing consistent power. Like most sealed lead-acid batteries, this design is very self-sufficient and doesn’t need a lot of maintenance. Shock and vibration resistance make this a decent travel battery and a good option for earthquake-prone locations.
The included 1-year warranty also offers added peace of mind with this battery. You’ll have some time to make sure it works as intended while it’s still covered by the manufacturer.
3. Gel Cell Deka 8G27 Gel Battery
- Sealed Valve Regulated.
- Spill-proof Gel Lead-Calcium.
- 12V Deep Cycle.
This gel battery manages to overcome most of the downsides of a gel battery system, making it one of the better options if you’re looking for a highly durable long-term energy storage solution. This design also tends to last longer than most gel batteries and has a comparable life span and power capacity to most lithium-ion batteries.
Like most gel batteries, this option is a little heavier than lithium-ion batteries, so it’s a good idea to have an assistant if you’re installing these batteries yourself.
Conclusion
Choosing the right solar-powered battery pack can make or break a great solar system, but it doesn’t have to be difficult. It might take a little time to figure out the best configuration for your power needs, but it’s time well-spent since a good solar system will lower your utility bills and your carbon footprint.
Whatever your reasons for upgrading to solar, hopefully, this article will help you pick the best solar battery bank for you.
