These are the three home batteries we install most often, and there is no single winner. They are built around different architectures and each one suits a different kind of home.
The honest version of this comparison is not “which battery is best.” It is “which battery fits your electrical situation, your backup goals and your existing equipment.” Below is what actually separates them.
| Specification | Tesla Powerwall 3 | Enphase IQ Battery 10C | FranklinWH aPower 2 |
|---|---|---|---|
|
Usable capacity per unit |
13.5 kWh |
10.0 kWh |
15 kWh |
|
Continuous power output |
Up to 11.5 kW |
7.08 kW |
10 kW |
|
Motor start capability |
Up to 185 A LRA |
Up to 90 A LRA |
185 A LRA |
|
Coupling |
DC coupled with integrated solar inverter, AC retrofit mode available |
AC coupled with embedded microinverters |
AC coupled |
|
Solar input |
Up to 20 kW DC, 6 MPPT |
None, pairs with existing system |
None, pairs with existing system |
|
Chemistry |
LFP |
LFP |
LFP |
|
Warranty |
10 years |
15 years or 6,000 cycles |
15 years or 60 MWh |
|
Required controller |
Gateway 3 or Backup Switch |
IQ System Controller |
aGate |
Figures reflect manufacturer published data at time of review. Confirm current specifications on the linked datasheets, since manufacturers revise products.
Is how much energy the battery holds. It determines how long you can run during an outage and how much evening peak usage you can cover.
Is how much the battery can deliver at once. Capacity decides how long. Power decides how much at the same time. A large battery with modest power output will run a fridge and lights for a long stretch but may struggle to start a large air conditioner.
is the one most homeowners have never heard of and the one that most often determines satisfaction. Motors draw a large surge at startup. Central air conditioning compressors, well pumps and pool pumps are the usual culprits in Southern California homes. The published gap here is meaningful: the Powerwall 3 and aPower 2 are both rated up to 185 A LRA, while the IQ Battery 10C is rated to around 90 A LRA.
If your home has central air and you want it to run during an outage, this specification matters more than capacity.
The Powerwall 3 integrates a solar inverter into the battery itself, accepting up to 20 kW of DC solar input across six MPPT channels. For a new solar and storage project built together, that consolidates equipment and simplifies the installation.
It delivers the highest continuous output of the three at up to 11.5 kW, which is why it handles large loads well without complex load shedding.
New solar plus storage installations, homes with substantial evening loads, and homeowners who want whole home backup from a single unit.
The 10 year warranty is shorter than the other two. Because the design is integrated, retrofitting onto an existing solar system needs careful compatibility review rather than an assumption that it will drop in.
The IQ Battery 10C is AC coupled with microinverters embedded in the battery. If your solar system already uses Enphase microinverters, this keeps everything on one platform with one monitoring app and one support path.
It is the most modular of the three, which makes it straightforward to size in increments and to expand later. The 15 year warranty is the longest term of the group.
Homes with existing Enphase solar, retrofits where AC coupling is preferred, and homeowners who want to start smaller and add capacity over time.
The lowest capacity and continuous output per unit of the three, and the lowest published motor start rating. Homes with central air conditioning generally need more than one unit or a carefully designed backup scope.
The aPower 2 holds the most energy per unit at 15 kWh and pairs with the aGate controller, which includes a built in transfer switch and manages the relationship between the grid, the battery, backed up loads and a generator if one is present.
It is AC coupled, which makes it flexible for retrofits onto most existing solar systems. It also stacks further than the other two, so large capacity requirements are easier to meet.
Whole home backup projects, larger retrofits, homes with a generator, and homeowners whose primary goal is outage resilience rather than rate arbitrage alone.
The largest physical footprint of the three, and the aGate adds a component and associated electrical work to the installation.
This is the platform we used on our Redondo Beach and Torrance whole home backup project, where the homeowner worked from home and needed reliability across the whole house rather than a few circuits.
The decision follows a fairly consistent path.
Start with the backup goal. Whole home or selected circuits? That question sets the required power output before capacity even enters the conversation.
Check the heavy loads. Central air, well pump, pool pump, EV charging. The motor start requirement often eliminates one option immediately.
Look at the existing system. An Enphase solar array points strongly toward staying on the Enphase platform. A home with no solar yet opens up the DC coupled route.
Then size capacity. How many evening peak hours you want to cover, and how long you want to run during an outage.
Finally, check the electrical service. Panel capacity, available space, and whether a subpanel or service upgrade is needed. This is frequently what determines real project cost, and it is often left out of quotes that look inexpensive.
There is no single best. The Powerwall 3 leads on power output and integrated design, the aPower 2 on capacity per unit and whole home backup, the IQ Battery 10C on modularity, warranty term and fit with existing Enphase systems.
It depends on your loads, not on a standard number. Whole home backup requires enough continuous power to run everything that may switch on at once, and enough capacity to sustain it. A load assessment answers this.
Usually yes. AC coupled batteries such as the IQ Battery 10C and aPower 2 are generally more straightforward for retrofits. Compatibility with your existing inverter needs checking first.
All three can support backup, but each requires its own controller and the right backup configuration. Backup capability depends on system design, not on the battery alone.
Motor start rating is the deciding factor. The Powerwall 3 and aPower 2 publish higher LRA ratings than the IQ Battery 10C. The specific compressor still needs to be checked against the design.
Ten years for the Powerwall 3, fifteen years or 6,000 cycles for the IQ Battery 10C, fifteen years or 60 MWh for the aPower 2. Terms, retention thresholds and conditions differ, so read the actual warranty document.
Green Additions designs and installs custom solar, battery storage, EV charging, and electrical solutions for Southern California homeowners.
Licensed California Solar Contractor
©2026 Green Additions | Designed and Develop By Designized.com
