Tesla Powerwall 2 vs Franklin WH aPower
The Franklin WH aPower wins this battery comparison by a clear margin. It delivers 13.6 kWh of usable storage with 5 kW continuous output and a 6,000-cycle rating, backed by a longer 12-year warranty. The 0.1 kWh capacity advantage provides 0 additional hours of essential-load backup.
Key Differences
- • Franklin WH aPower provides 13.6 kWh vs 13.5 kWh usable capacity.
- • Tesla Powerwall 2 achieves 90% round-trip efficiency vs 89%.
- • Franklin WH aPower offers a longer 12-year warranty vs 10 years.
- • Franklin WH aPower is rated for 6,000 cycles vs 5,000.
Specifications Breakdown
Usable Storage Capacity
The Tesla Powerwall 2 provides 13.5 kWh of usable capacity (14 kWh total, 100% DoD), while the Franklin WH aPower offers 13.6 kWh usable (13.6 kWh total, 100% DoD). At an average essential-load consumption rate of 750 watts, the Tesla Powerwall 2 provides approximately 18.0 hours of backup versus 18.1 hours for the Franklin WH aPower. The Franklin WH aPower's 0.1 kWh capacity advantage translates to roughly 0 additional hours of essential-load backup during a grid outage. The Tesla Powerwall 2 is scalable up to 10 units (135 kWh total), while the Franklin WH aPower scales up to 15 units (204 kWh total).
Power Output
The Tesla Powerwall 2 delivers 5 kW continuous and 7 kW peak power, while the Franklin WH aPower provides 5 kW continuous and 10 kW peak. Matched power output means both can run the same combination of appliances simultaneously. Peak power rating matters for motor-driven loads with high startup current, such as air conditioners, well pumps, and sump pumps. The Franklin WH aPower's 10 kW peak is capable of starting most residential HVAC systems.
Battery Chemistry & Cycle Life
The Tesla Powerwall 2 uses NMC chemistry with a rated cycle life of 5,000 cycles (approximately 13.7 years of daily cycling), while the Franklin WH aPower uses LFP with 6,000 cycles (approximately 16.4 years). LFP (Lithium Iron Phosphate) offers superior thermal stability with zero risk of thermal runaway, longer cycle life, no cobalt dependency, and tolerance for 100% depth of discharge. NMC (Nickel Manganese Cobalt) provides higher energy density in a smaller and lighter package but has shorter cycle life and requires more conservative depth-of-discharge management. The Franklin WH aPower's additional 1,000 cycles translates to approximately 2.7 more years of daily use before reaching the rated end of life.
Round-Trip Efficiency
The Tesla Powerwall 2 achieves 90% round-trip efficiency versus 89% for the Franklin WH aPower. This means for every 10 kWh of solar energy stored in the Tesla Powerwall 2, 9.0 kWh is recoverable, compared to 8.9 kWh for the other. Over 10 years of daily cycling with 15 kWh average daily throughput, the more efficient battery saves approximately $82 in energy that would otherwise be lost as heat (at $0.15/kWh average retail rate). Higher round-trip efficiency is especially valuable in time-of-use rate environments where you are storing cheap off-peak energy for expensive peak-hour consumption.
Warranty & Long-Term Protection
The Tesla Powerwall 2 carries a 10-year warranty and 37.8 MWh throughput, while the Franklin WH aPower offers 12 years and 43 MWh throughput. The Franklin WH aPower provides 2 additional years of manufacturer protection against capacity degradation and defects. Battery warranties typically guarantee the unit will retain 60-70% of original capacity by end of warranty, so the length of coverage directly impacts your financial risk over the system's lifetime.
Specification Comparison
| Specification | Tesla Powerwall 2 | Franklin WH aPower |
|---|---|---|
| Capacity | 14 kWh | 13.6 kWh |
| Usable Capacity | 13.5 kWh | 13.6 kWh |
| Power Output | 5 kW | 5 kW |
| Chemistry | NMC (Nickel Manganese Cobalt) | LFP (Lithium Iron Phosphate) |
| Efficiency | 90% | 89% |
| Cycle Life | 5,000 | 6,000 |
| Weight | 114 kg | 130 kg |
| Warranty | 10 years | 12 years |
| Scalable | Yes | Yes |
5-Dimension Head-to-Head Analysis
1. Storage Capacity
Winner: Franklin WH aPowerThe Franklin WH aPower provides 13.6 kWh versus 13.5 kWh — 0.1 kWh more usable storage. At typical essential-load consumption of 0.75 kW, this equals approximately 0 additional hours of backup power. The capacity difference is moderate.
2. Power Output
Winner: TieBoth deliver 5 kW continuous output — identical ability to power household loads simultaneously.
3. Chemistry & Longevity
Winner: Franklin WH aPowerThe Franklin WH aPower uses LFP chemistry (6,000 cycles, safer, longer-lasting) while the Tesla Powerwall 2 uses NMC (5,000 cycles, higher energy density). LFP is the clear technology winner for residential storage: it offers 50-100% more cycles, zero thermal runaway risk, no cobalt, and 100% depth of discharge. NMC's only advantage is a lighter, more compact form factor.
4. Round-Trip Efficiency
Winner: Tesla Powerwall 2The Tesla Powerwall 2 achieves 90% round-trip efficiency versus 89%. Over 10 years of daily cycling with 15 kWh throughput per day, the more efficient battery saves approximately 82 dollars in energy that would otherwise be lost as heat (at $0.15/kWh). The difference is moderate but compounds over the battery's lifespan.
5. Warranty Coverage
Winner: Franklin WH aPowerThe Franklin WH aPower offers a 12-year warranty versus 10 years. Consider the remaining warranty period when evaluating total cost of ownership.
Tesla Powerwall 2
The Tesla Powerwall 2 was discontinued in November 2025 after nearly a decade as the world's most popular home battery. First released in 2016, it established Tesla as the leader in residential energy storage with over a million units installed globally (including Powerwall+). It uses NMC chemistry with liquid cooling and delivers 5 kW continuous power (5.8 kW on late models produced after November 2020, with 10 kW peak). As an AC-coupled system, it retrofits easily onto existing solar installations without replacing the inverter. Up to ten units can be stacked for 135 kWh / 50 kW systems. Tesla continues to honor the 10-year / 37.8 MWh throughput warranty for existing units. For new installations, the Powerwall 3 is the recommended replacement.
Pros
- + Proven reliability with over a million global installations since 2016
- + AC-coupled design retrofits with any existing solar inverter brand
- + Supports up to 10 units for 135 kWh / 50 kW system capacity
- + Tesla continues full warranty support and software updates for existing units
Cons
- - Discontinued November 2025 — no longer available for new installations
- - Lower 5 kW continuous power output compared to Powerwall 3's 11.5 kW
- - NMC chemistry has shorter cycle life than newer LFP alternatives
- - Late-model power improvements (5.8 kW / 10 kW peak) not available on early units
Franklin WH aPower
The Franklin WH aPower is a 13.6 kWh LFP battery designed to work with the Franklin aGate energy management gateway for comprehensive whole-home energy control. Its 10 kW peak power capability handles demanding startup surges from appliances like air conditioners and well pumps. With support for up to 15 units, the system scales to 204 kWh for commercial-grade residential applications. The inverter-agnostic AC-coupled design makes it compatible with virtually any existing solar installation, making it one of the most flexible battery options available. Franklin backs it with a 12-year warranty and 43 MWh throughput guarantee.
Pros
- + Exceptional scalability with up to 15 units for 204 kWh total capacity
- + 10 kW peak power handles heavy appliance startup surges
- + Inverter-agnostic AC-coupled design works with any solar system
- + 12-year warranty with 43 MWh throughput guarantee exceeds industry standard
Cons
- - Requires the separate aGate unit for full backup and management features
- - 89% round-trip efficiency is below average for LFP batteries
- - 5 kW continuous output per unit is modest for the capacity
Choose Tesla Powerwall 2 If...
- ✓ You want to minimize energy losses during daily charge/discharge cycling
- ✓ No longer available for new installations. Existing Powerwall 2 owners should continue using their units under warranty. For new battery storage, see the Tesla Powerwall 3.
Choose Franklin WH aPower If...
- ✓ You need more backup storage to cover overnight consumption or extended outages
- ✓ Maximum battery longevity (6,000 cycles) is your top priority
- ✓ A 12-year warranty gives you the confidence you need
- ✓ You want the flexibility to expand storage capacity over time (up to 15 units)
- ✓ Battery safety and thermal stability are your primary concerns
Our Recommendation
We recommend the Franklin WH aPower for most buyers in this comparison. It wins 3 of 5 key dimensions and offers a clear advantage in the metrics that matter most for a battery purchase. The Tesla Powerwall 2 remains a good product, but the Franklin WH aPower delivers better overall value for the majority of installations.
Frequently Asked Questions
Which is better, Tesla Powerwall 2 or Franklin WH aPower?
The Franklin WH aPower wins this battery comparison by a clear margin. It delivers 13.6 kWh of usable storage with 5 kW continuous output and a 6,000-cycle rating, backed by a longer 12-year warranty. The 0.1 kWh capacity advantage provides 0 additional hours of essential-load backup.
Which battery lasts longer?
The Tesla Powerwall 2 is rated for 5,000 cycles versus 6,000 for the Franklin WH aPower. Franklin WH aPower lasts approximately 3 more years of daily cycling. LFP chemistry generally outlasts NMC in cycle life testing.
Which battery provides more backup power?
The Tesla Powerwall 2 provides 5 kW continuous (7 kW peak) versus 5 kW continuous (10 kW peak) for the Franklin WH aPower. Both deliver identical continuous power. A central AC typically needs 3-5 kW, a refrigerator 0.2 kW, and an EV charger 7-11 kW.
Can I expand Tesla Powerwall 2 or Franklin WH aPower storage later?
Tesla Powerwall 2: Yes, up to 10 units for 135 kWh total. Franklin WH aPower: Yes, up to 15 units for 204 kWh total. Franklin WH aPower offers more expansion potential.
Which battery chemistry is safer?
Franklin WH aPower uses LFP chemistry, which is safer — LFP cells do not undergo thermal runaway and are inherently thermally stable. Tesla Powerwall 2 uses NMC chemistry, which has higher energy density but requires more sophisticated thermal management. Both are UL 9540 certified and safe for residential use.
Related Resources
Last updated: February 2026