The Home Battery ReportIndependent · No installer money

FranklinWH aPower 2 vs Generac PWRcell

A straight, side by side read on specs and warranties, with the honest caveats. Every figure is from the manufacturer datasheet; sources are at the bottom.

Figure - Specs to scalebars vs the largest in our database
FranklinWH aPower 2 versus Generac PWRcell: specs to scaleHorizontal bars comparing usable capacity, continuous power, peak power, warranty for FranklinWH aPower 2 and Generac PWRcell, each scaled against the largest value in the home battery database.FranklinWH aPower 2Generac PWRcellUsable capacity15 kWhup to 18 kWhContinuous power10 kW10.5 kWPeak power15 kWNot publishedWarranty15 yr10 yr
SpecFranklinWH aPower 2Generac PWRcell
ChemistryLFPNMC
Usable capacity15 kWhup to 18 kWh
Continuous power10 kW10.5 kW
Peak power15 kWNot published
Round-trip efficiency90%88%
Warranty15 years or 60 MWh throughput, whichever comes first10 years or 7.56 MWh throughput per module
Backup scopeWhole-home capableWhole-home capable
InverterIntegratedIntegrated

What actually differs

  • More usable capacity: the Generac PWRcell offers up to 18 kWh vs 15 kWh (its largest single cabinet; the base config is smaller), so at that size it carries more of your home for longer per charge.
  • More continuous power: the Generac PWRcell sustains 10.5 kW vs 10 kW, which matters for running big loads like an AC at once.
  • Longer warranty term: the FranklinWH aPower 2 is warranted 15 years vs 10, though always read the throughput or cycle cap too.
  • Different chemistry: the FranklinWH aPower 2 is LFP and the Generac PWRcell is NMC. For a battery that never moves, LFP's safety and cycle life usually beat NMC's higher energy density.
  • Efficiency is not apples to apples here: the FranklinWH aPower 2 quotes 90% (grid to battery to load (AC round trip)) and the Generac PWRcell quotes 88% (system round trip), so do not read the raw numbers as a direct ranking.

Which one pays off is a numbers question.

Neither spec sheet tells you the payback in your home. That comes from your rate plan and incentives.

Run the Worth It calculator →

Sources

Source: FranklinWH aPower 2 datasheet, Dec 2025. Specs verified 2026-07-01. Figures are per single unit at beginning of life; confirm the current datasheet with your installer.

Source: Generac PWRcell 2 spec sheet, Jul 2025. Specs verified 2026-07-01. Figures are per single unit at beginning of life; confirm the current datasheet with your installer.