Solar Batteries in 2024
Solar batteries play a crucial role in storing excess energy generated by your solar power system for later use. They enhance the efficiency of your solar setup and can provide backup power when needed. In this comprehensive guide, we present the top six solar batteries for residential homes, along with essential details about each battery's specifications.
Solar Battery Chart
To make it easier to compare the key specifications of each solar battery, we've compiled the following chart:
Battery | Usable Capacity (kWh) | Continuous Power Rating (kW) | Round-Trip Efficiency | Depth of Discharge (DoD) | Warranty |
SunPower SunVault | 12 kWh | 6.8 kW | 85% | Not disclosed | 10 years |
Tesla Powerwall 2 | 13.5 kWh | 5 kW | 90% | 100% | 10 years (unlimited cycles) |
LG Chem RESU | 9.8 kWh | 5 kW | 94.5% | 95% | 10 years |
Enphase IQ | Varies by model | Varies by model | 96% | 100% | 10 years |
Generac PWRcell | Varies by model | Varies by model | 96.5% | 84% | 10 years |
Sonnen Eco | Varies by model | Varies by model | 81.6% | 90% | 10 years |
Now, let's delve into the details of each solar battery.
Highest Usable Capacity: SunPower SunVault
RATING: 4/5
What we like: SunPower's SunVault offers a high usable capacity of 12 kWh with a continuous power rating of 6.8 kW. While it boasts a round-trip efficiency of 85%, the depth of discharge (DoD) is not disclosed. SunVault comes with a 10-year warranty and has an end-of-warranty capacity of 70%.
Benefits
Better-than-average end-of-warranty capacity
Compatible with existing solar systems
Largest usable capacity among reviewed LFP batteries
Drawbacks
Exclusive to SunPower solar systems
Lower round-trip efficiency compared to other models
Undisclosed DoD information
Best Warranty Coverage: Tesla Powerwall 2
RATING: 4.65 out of 5 stars
What we like: The Tesla Powerwall 2 offers a 13.5 kWh capacity and a continuous power rating of 5 kW. It stands out with a 90% round-trip efficiency and an impressive 100% depth of discharge (DoD). Tesla provides a leading 10-year warranty with unlimited cycles.
Benefits
Compatible with existing solar systems
Outstanding warranty coverage
Modular options for expanding backup power
Drawbacks
Delayed wait times for Powerwall orders
Limited availability through Tesla and its dealer network
No modular options
Best Brand Reputation: LG Chem RESU
RATING: 4.65 out of 5 stars
What we like: LG Chem RESU-10H offers a usable capacity of 9.8 kWh and a continuous power rating of 5 kW. It excels with a 94.5% round-trip efficiency and a 95% depth of discharge (DoD). The 10-year warranty includes a throughput clause of 22.4 MWh.
Benefits
Better availability than other battery systems
Highly efficient NMC battery
10-year warranty with reasonable throughput clause
Drawbacks
Lower end-of-warranty capacity
Not suitable for high-energy needs
Throughput clause is lower than other models
Best Lower Power Option: Enphase IQ
RATING: 4.65 out of 5 stars
What we like: Enphase IQ offers modular battery options, with varying capacities and continuous power ratings. It comes in four models with impressive 96% round-trip efficiency and a 100% depth of discharge (DoD). Enphase provides a 10-year warranty with a 4,000-cycle clause.
Benefits
High DoD and round-trip efficiency
Compatibility with solar and gas-powered generators
Modular battery choices
Drawbacks
Additional costs for extended warranty coverage
Not suitable for high-capacity homes
Requires use with an Enphase inverter
Best Round-Trip Efficiency: Generac PWRcell
RATING: 4.5 out of 5 stars
What we like: Generac PWRcell offers various system options with customizable configurations. It uses 3-kWh modules, allowing for flexibility in storage capacity. The PWRcell battery boasts a 96.5% round-trip efficiency, though it has a lower 84% depth of discharge (DoD). It comes with a 10-year warranty with varying throughput clauses.
Benefits
Better customization with smaller modules
Highest DoD among reviewed batteries
Includes a protective cabinet for indoor and outdoor installations
Drawbacks
Incompatible with existing solar systems
Lower DoD compared to other options
Performance may be affected in extreme temperatures
Best Customization: Sonnen Eco
RATING: 4.8 out of 5 stars
What we like: Sonnen Eco offers extensive modular battery options, allowing for greater customization. With 2.5-kWh modules, you can start with a 5-kWh backup system and expand it up to 20 kWh. It features an 81.6% round-trip efficiency and a 90% depth of discharge (DoD). Sonnen Eco batteries are backed by a 10-year warranty and a 10,000-cycle clause.
Benefits
10-year warranty with high DoD
Seven modular battery options for tailored storage
Suitable for larger installations
Drawbacks
Heavier than other battery options
Lower continuous power rating than some models
Not ideal for homes with limited space or indoor installations
Types of Solar Batteries
When considering solar batteries, it's essential to understand the different types available:
Lead-Acid Batteries:
These have a long history in the solar industry and are known as deep cycle batteries. They can charge and discharge continuously but have limitations, including a lower depth of discharge (typically 50%) and a shorter lifespan (around 3-5 years). Lead-acid batteries are suitable for off-grid installations.
Lithium-Ion Batteries:
More commonly used, lithium-ion batteries are efficient and versatile. They offer higher depth of discharge, quicker charging, and longer lifespans compared to lead-acid batteries. They are a preferred choice for most solar setups.
In summary, selecting the right solar battery depends on your specific energy needs, budget, and system requirements. It's essential to consider factors such as capacity, efficiency, warranty, and compatibility with your existing solar setup when making your decision. Solar Batteries in 2024