A power bank advertised as 20000mAh may deliver a smaller milliamp-hour figure at its USB output without anything being missing.
Your 20000mAh Power Bank Does Not Deliver 20000mAh at USB Voltage Read Post »
Battery percentage is an estimate of remaining usable capacity, not a direct view inside the cells.
Battery Percentage Jumps After a Restart? The Gauge Is Making an Estimate Read Post »
A battery-powered device can run for less time in the cold even when its battery is not permanently worn out.
Cold Weather Steals Battery Runtime—Even Before the Battery Is Worn Out Read Post »
A battery can show a plausible voltage with no load and collapse when the device starts.
A Battery Has Voltage but Cannot Run the Device? Look at Internal Resistance Read Post »
A device with several replaceable batteries works as a set.
Why Two New Batteries and One Old Battery Are a Bad Team Read Post »
Rechargeable AA batteries commonly say 1.2V while alkaline AAs say 1.5V.
Rechargeable AAs Say 1.2V—So Why Do They Work in 1.5V Devices? Read Post »
A 100W label is a capability claim, not a promise that your laptop will receive 100W.
Why a 100W Charger Can Still Charge Your Laptop Slowly Read Post »
A swollen lithium battery is a physical fault, not merely a disappointing runtime figure.
Battery Swelling Is Not Just Lost Capacity—Here Is What Changes Read Post »
Your laptop charges normally until you plug a phone into the same charger.
Your Multiport Charger Gets Slower When You Add a Phone—Here Is Why Read Post »
A battery pack can reach its cutoff while some cells still contain useful energy.
Why a Battery Pack Can Stop Working Before Every Cell Is Empty Read Post »
