The ever-evolving world of power stations and battery technology makes for a wide range of options, ranging from the latest and greatest advancements to products that might already be fading out of relevance. To ensure our lineup is dialed, we scoured reviews and online forums and spent countless hours researching each model for our review. Once each model was decided, our team devised a game plan to test each power station based on importance and relevance, mixing real-world tests with purpose-built benchmark testing. Our testing aims to help simplify and streamline the decision-making process when in the market for a portable power station.
Power Efficiency
The most heavily weighted metric in our tests is our power efficiency metric, which focuses on each model's power efficiency and testing the AC inverter's max output. This gives us a good idea of how effectively each power station is utilizing its advertised capacity and is typically the most important factor when deciding what type of devices and appliances you can run.
Using an AC load bank we designed and built in-house, our team could precisely control the amount of power drawn from each power station's system. Our most heavily weighted test measured each power station's overall efficiency. If the power station's battery had a 200Wh rating, we would expect it to run 200 watts for one full hour. We applied a 200W load and measured how long the load ran. We then take the tested run time and divide by 60 minutes to report the result as a percentage. So a 55 min test /60 min expected = 91.6% usable capacity. It's all but guaranteed that none of the power stations achieve a 100% usable capacity. There are a variety of reasons for this, such as BMS protections from the manufacturer, the inverter drawing additional power, the display drawing additional power, the internal battery management system drawing additional power, etc. This test gives us a better picture of the available usable capacity in a more real-world scenario.
Our other power output tests involve running each power station at its maximum inverter rating and recording how long it runs. We also accounted for the power density of each unit by identifying the weight of each station compared to its watt-hour rating. This gives us a better idea of how weight is distributed towards power versus other aspects of each station. Lastly, we accounted for the number of AC and DC ports equipped in each unit, which contributed to the overall power output score.
Additionally, we use our AC Load Bank to test how long the power station can output its maximum power. You might see some surprising results here due to design variation from one manufacturer to another. Some models come equipped with high-powered inverters relative to their battery size. This means they can dump all of their battery capacity quickly when running at full power.
Charge Speed
Without a doubt, charge speed is one of the most important factors to consider when deciding on a portable power station. Luckily for us, testing charge time is a straightforward, easily quantifiable process. Our team accounted for the wide range of battery sizes in our test group by dividing the battery size (watt hours) by its charge time, giving us an average rate of charge for each power station. We also noted any significant charging features equipped on each model. Some brands offer increased charging speeds by toggling a button either on the power station itself or through a mobile app. Some models also allow for simultaneous charging, such as combining solar and AC or AC and USB.
Mobility
Portable power stations, as the name implies, are typically portable enough to carry and load between cars, campsites, and garages. However, besides the obvious discrepancies in weight, many models utilize their design to help offset weight, such as handle design, built-in wheels, and overall shape. Some of the smaller power stations we tested weigh less than eight pounds and are easily stashed in backpacks and bags. Some of the larger power stations tested require multiple people just to lift them into the car. All that said, our mobility testing covered a large variance in overall size and portability.
For our more objective data, we used heavy-duty hanging scales to measure weight. We also tossed these power stations into different cars, packed them away for a week of camping, and rolled them across uneven terrain to assess how effective their design is when using them out in the real world. We also gathered input from multiple individuals to get feedback on each model's handle and carrying feel to get a better consensus on how each model performed when being lifted and handled.
Ease of Use
With so many different features advertised by manufacturers, it can be hard to decipher which features and display units are worth the hype and which ones are better off without. We set out to test ease of use by identifying features with the most value and applicability. This included whether each station had a built-in light, the inclusion of a smartphone app, expansion capabilities, bypass mode, and uninterruptible or emergency power supply features. We also spent time interacting and scoring each unit's display and screen. Within our display scoring test, we considered models that included important screen functions such as charging information and wattage input/output. While some models do an excellent job of providing this information, others have severely limited displays. Finally, we made sure to account for each screen's overall size and illumination. At first, it may not seem like the most important feature, but it does become super beneficial under low-light scenarios, such as during a power outage.
