Franklin WH aPower vs HomeGrid Stack'd Series 38.4kWh

Our Verdict Winner: HomeGrid Stack'd Series 38.4kWh

The HomeGrid Stack'd Series 38.4kWh wins this battery comparison by a decisive margin. It delivers 38.4 kWh of usable storage with 34.4 kW continuous output and a 6,000-cycle rating. The 24.8 kWh capacity advantage provides 33 additional hours of essential-load backup.

Power / Capacity
13.6 kWh
vs
38.4 kWh
Efficiency
89%
vs
96%
Warranty
12 yrs
vs
10 yrs

Key Differences

  • HomeGrid Stack'd Series 38.4kWh provides 38.4 kWh vs 13.6 kWh usable capacity.
  • HomeGrid Stack'd Series 38.4kWh achieves 96% round-trip efficiency vs 89%.
  • Franklin WH aPower offers a longer 12-year warranty vs 10 years.

Specifications Breakdown

Usable Storage Capacity

The Franklin WH aPower provides 13.6 kWh of usable capacity (13.6 kWh total, 100% DoD), while the HomeGrid Stack'd Series 38.4kWh offers 38.4 kWh usable (38.4 kWh total, 100% DoD). At an average essential-load consumption rate of 750 watts, the Franklin WH aPower provides approximately 18.1 hours of backup versus 51.2 hours for the HomeGrid Stack'd Series 38.4kWh. The HomeGrid Stack'd Series 38.4kWh's 24.8 kWh capacity advantage translates to roughly 33 additional hours of essential-load backup during a grid outage. The Franklin WH aPower is scalable up to 15 units (204 kWh total), while the HomeGrid Stack'd Series 38.4kWh scales up to 15 units (576 kWh total).

Power Output

The Franklin WH aPower delivers 5 kW continuous and 10 kW peak power, while the HomeGrid Stack'd Series 38.4kWh provides 34.4 kW continuous and 50 kW peak. The HomeGrid Stack'd Series 38.4kWh's higher continuous output means it can simultaneously power more demanding appliances during an outage. A central air conditioner typically draws 3-5 kW, a refrigerator 0.1-0.2 kW, and an EV Level 2 charger 7-11 kW. Peak power rating matters for motor-driven loads with high startup current, such as air conditioners, well pumps, and sump pumps. The HomeGrid Stack'd Series 38.4kWh's 50 kW peak is capable of starting most residential HVAC systems.

Battery Chemistry & Cycle Life

The Franklin WH aPower uses LFP chemistry with a rated cycle life of 6,000 cycles (approximately 16.4 years of daily cycling), while the HomeGrid Stack'd Series 38.4kWh uses LFP with 6,000 cycles (approximately 16.4 years). Both use LFP chemistry, which is considered the gold standard for residential energy storage due to its inherent safety, long cycle life, and environmental friendliness. Identical cycle ratings mean both batteries have the same expected operational lifespan under daily cycling.

Round-Trip Efficiency

The Franklin WH aPower achieves 89% round-trip efficiency versus 96% for the HomeGrid Stack'd Series 38.4kWh. This means for every 10 kWh of solar energy stored in the HomeGrid Stack'd Series 38.4kWh, 9.6 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 $575 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 Franklin WH aPower carries a 12-year warranty and 43 MWh throughput, while the HomeGrid Stack'd Series 38.4kWh offers 10 years. 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 Franklin WH aPower HomeGrid Stack'd Series 38.4kWh
Capacity 13.6 kWh 38.4 kWh
Usable Capacity 13.6 kWh 38.4 kWh
Power Output 5 kW 34.4 kW
Chemistry LFP (Lithium Iron Phosphate) LFP (Lithium Iron Phosphate)
Efficiency 89% 96%
Cycle Life 6,000 6,000
Weight 130 kg 268 kg
Warranty 12 years 10 years
Scalable Yes Yes

5-Dimension Head-to-Head Analysis

1. Storage Capacity

Winner: HomeGrid Stack'd Series 38.4kWh

The HomeGrid Stack'd Series 38.4kWh provides 38.4 kWh versus 13.6 kWh — 24.8 kWh more usable storage. At typical essential-load consumption of 0.75 kW, this equals approximately 33 additional hours of backup power. This is a substantial capacity gap.

2. Power Output

Winner: HomeGrid Stack'd Series 38.4kWh

The HomeGrid Stack'd Series 38.4kWh delivers 34.4 kW continuous versus 5 kW. This is enough to run a central AC unit, refrigerator, and general household loads simultaneously. The 29.4 kW power gap significantly impacts what appliances you can run during outages.

3. Chemistry & Longevity

Winner: Tie

Both use LFP chemistry with identical 6,000-cycle ratings. LFP chemistry provides excellent thermal stability, long cycle life, and no cobalt dependency.

4. Round-Trip Efficiency

Winner: HomeGrid Stack'd Series 38.4kWh

The HomeGrid Stack'd Series 38.4kWh achieves 96% round-trip efficiency versus 89%. Over 10 years of daily cycling with 15 kWh throughput per day, the more efficient battery saves approximately 575 dollars in energy that would otherwise be lost as heat (at $0.15/kWh). This efficiency gap is significant and meaningfully impacts lifetime economics.

5. Warranty Coverage

Winner: Franklin WH aPower

The Franklin WH aPower offers a 12-year warranty versus 10 years. Consider the remaining warranty period when evaluating total cost of ownership.

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
View full Franklin WH aPower specs →

HomeGrid Stack'd Series 38.4kWh

The HomeGrid Stack'd Series 38.4kWh is the maximum single-stack configuration with 8 modules. Delivering 34.4 kW continuous and 50 kW peak power with 38.4 kWh capacity, it provides multi-day backup capability for energy-intensive homes pursuing full off-grid or near-off-grid living.

Pros

  • + 38.4 kWh provides multi-day backup for most homes
  • + 34.4 kW continuous output surpasses most residential needs
  • + Still expandable — up to 15 stacks in parallel for 576 kWh
  • + Highest energy density per stack in the 48V residential category

Cons

  • - 268kg requires reinforced concrete pad or heavy-duty rack
  • - Maximum stack height may require ceiling clearance planning
  • - Very high current draw at peak — requires heavy gauge wiring
View full HomeGrid Stack'd Series 38.4kWh specs →

Choose Franklin WH aPower If...

  • A 12-year warranty gives you the confidence you need
  • Homeowners who need massive scalability and inverter-agnostic compatibility with a focus on whole-home backup

Choose HomeGrid Stack'd Series 38.4kWh If...

  • You need more backup storage to cover overnight consumption or extended outages
  • You need to power demanding appliances (AC, EV charger) simultaneously during outages
  • You want to minimize energy losses during daily charge/discharge cycling
  • Off-grid homes, preppers, and energy-intensive households seeking maximum battery autonomy

Our Recommendation

Recommended HomeGrid Stack'd Series 38.4kWh

The HomeGrid Stack'd Series 38.4kWh is the decisive winner in this battery comparison, outperforming the Franklin WH aPower in 3 of 5 dimensions. Unless you have a specific requirement that the Franklin WH aPower uniquely addresses, the HomeGrid Stack'd Series 38.4kWh is the stronger choice for virtually every installation scenario.

Frequently Asked Questions

Which is better, Franklin WH aPower or HomeGrid Stack'd Series 38.4kWh?

The HomeGrid Stack'd Series 38.4kWh wins this battery comparison by a decisive margin. It delivers 38.4 kWh of usable storage with 34.4 kW continuous output and a 6,000-cycle rating. The 24.8 kWh capacity advantage provides 33 additional hours of essential-load backup.

Which battery lasts longer?

The Franklin WH aPower is rated for 6,000 cycles versus 6,000 for the HomeGrid Stack'd Series 38.4kWh. Both have identical expected cycle life. LFP chemistry generally outlasts NMC in cycle life testing.

Which battery provides more backup power?

The Franklin WH aPower provides 5 kW continuous (10 kW peak) versus 34.4 kW continuous (50 kW peak) for the HomeGrid Stack'd Series 38.4kWh. HomeGrid Stack'd Series 38.4kWh can run more appliances simultaneously during an outage. A central AC typically needs 3-5 kW, a refrigerator 0.2 kW, and an EV charger 7-11 kW.

Can I expand Franklin WH aPower or HomeGrid Stack'd Series 38.4kWh storage later?

Franklin WH aPower: Yes, up to 15 units for 204 kWh total. HomeGrid Stack'd Series 38.4kWh: Yes, up to 15 units for 576 kWh total. Both offer the same scalability.

Which battery chemistry is safer?

Both use LFP (Lithium Iron Phosphate) chemistry, which is the safest lithium battery chemistry for residential use. LFP does not undergo thermal runaway, uses no cobalt, and is inherently stable.

Related Resources

Last updated: February 2026