Home Battery Comparison — FranklinWH vs EG4 vs Sigenergy vs APsystems
Choosing the right battery storage system depends on your inverter, installation environment, budget, and how much capacity you need. This page compares every battery we stock at Solwel side by side so you can make the right call for your project.
Need help choosing? Call us at (346) 432-4228 or request a quote.
Side-by-Side Spec Comparison
| Spec | FranklinWH aPower 2 | EG4 WallMount 280Ah | Sigenergy SigenStor 6kWh | Sigenergy SigenStor 9kWh | APsystems APStorage 10kWh |
|---|---|---|---|---|---|
| Usable Capacity | 15 kWh | 14.3 kWh | 6 kWh | 9 kWh | 10 kWh |
| Continuous Power | 10 kW | Inverter-dependent | Inverter-dependent | Inverter-dependent | Inverter-dependent |
| Chemistry | LFP | LFP | LFP | LFP | LFP |
| Max Expandability | 75 kWh (5 units) | Inverter-limited | Stackable | Stackable | Stackable |
| Inverter Compatibility | FranklinWH aGate X | EG4 + many third-party | Sigenergy only | Sigenergy only | APsystems ELS PCS |
| Coupling Type | AC-coupled | DC-coupled | DC-coupled | DC-coupled | AC-coupled |
| Enclosure Rating | Indoor only | IP55 (indoor/outdoor) | Indoor wall-mount | Indoor wall-mount | Indoor |
| Cooling | Passive — 30 dBA | Active | Active | Active | Active |
| Warranty | 12 years | 10 years | 10 years | 10 years | 10 years |
| Best For | Retrofits, noise-sensitive | EG4 systems, outdoor | Modular growth | Modular growth | APsystems systems |
Which Battery Is Right for Your Project?
FranklinWH aPower 2 — Best for Retrofits & Noise-Sensitive Installs
The aPower 2 is AC-coupled, meaning it connects to the home's AC bus via the aGate X gateway rather than the inverter's DC input. This makes it ideal for retrofitting battery storage onto an existing grid-tied solar system without replacing the inverter. Its passive cooling runs at just 30 dBA — quieter than a refrigerator — making it the only residential battery genuinely suitable for finished living spaces. At 12 years, it also carries the longest warranty in this comparison.
EG4 WallMount 280Ah — Best for EG4 Systems & Outdoor Installs
The EG4 WallMount is the natural pairing for EG4 hybrid inverters and offers the widest third-party inverter compatibility of any battery in this lineup. Its IP55 outdoor rating makes it the only battery here that can be wall-mounted in unconditioned spaces, exterior utility areas, or covered outdoor locations — a significant installation flexibility advantage on projects where indoor space is limited.
Sigenergy SigenStor Battery Packs — Best for Sigenergy Systems & Phased Budgets
SigenStor battery packs are exclusively compatible with the Sigenergy SigenStor inverter — they're part of a fully integrated ecosystem. The modular 6 kWh and 9 kWh pack sizes make it easy to start small and expand as budget allows. If your customer is going all-in on the Sigenergy ecosystem (including V2H EV charging), these are the obvious choice.
APsystems APStorage 10kWh — Best for APsystems Microinverter Systems
The APStorage is designed to pair with the APsystems ELS 11.4K PCS, making it the natural storage solution for installers already working with APsystems microinverters. It's AC-coupled and integrates directly with the APsystems EMA monitoring platform.
Battery Storage Bundles
Need a complete system? We offer pre-packaged Sigenergy whole-home backup bundles:
- Sigenergy 15 kWh Stack Bundle
- Sigenergy 27 kWh Stack Bundle
- Sigenergy 36 kWh Stack Bundle
- Sigenergy 54 kWh Stack Bundle
Still Not Sure? Talk to Our Team.
We work with solar installers and contractors every day. Call us at (346) 432-4228, email info@solwel.com, or submit a quote request and we'll help you choose the right battery for your project.