Capacity & Power Output
25
Evaluates total watt-hour capacity, continuous AC output watts, and surge handling capability. Higher scores for units that deliver rated output consistently and handle startup surges from motors and compressors.
Data sources: Manufacturer spec sheets, independent bench tests, verified user reports
Value for Money
20
Cost-per-watt-hour analysis relative to competing products in the same price tier. Factors in build quality, included accessories, warranty length, and long-term ownership cost including battery replacement.
Data sources: Live Amazon pricing, manufacturer MSRP, warranty terms
Solar Charging Performance
15
Maximum solar input wattage, MPPT charge controller efficiency, voltage range compatibility, and real-world charging speed under standard test conditions. Includes connector ecosystem and compatibility with third-party panels.
Data sources: Manufacturer MPPT specs, solar input curves, user-reported charge times
Portability & Build Quality
15
Weight-to-capacity ratio, form factor, handle/ergonomic design, IP rating (weather resistance), chassis material quality, and vibration damping. Higher scores for units that travel well without sacrificing durability.
Data sources: Measured weight, IP certification data, user durability reports
Expandability & Feature Set
15
Battery expansion capability, number and variety of output ports (AC, USB-C, USB-A, 12V DC), app connectivity and monitoring features, UPS mode capability, and any unique features that add practical value.
Data sources: Spec sheets, port inventory, app store ratings for companion apps
Battery Chemistry & Longevity
10
Battery chemistry (LiFePO4 vs NMC vs lead-acid), rated cycle life at 80% depth of discharge, thermal stability, storage characteristics, and warranty terms. LiFePO4 units score higher due to longer cycle life and better safety profile.
Data sources: Battery datasheets, cycle life certifications, warranty terms