Do you really understand laptop batteries and power adapters?

　　Many laptops have similar hardware configurations, but differ significantly in battery life or performance. In fact, the battery life of a notebook depends largely on the battery; the actual performance is also affected by the power of the power adapter. If you want to know these two hardwares, you need to start with their basic parameters.

　　Laptop's battery

　　The battery life of a notebook is mainly affected by two aspects. One is the power consumption of the entire hardware platform of the notebook, including hardware units such as screen, processor, graphics card, memory, hard disk and speakers. Among them, the processor and graphics card are big power consumers, and the battery life of thin and light notebooks can generally reach more than three times that of gaming notebooks, because the thin and light notebooks are equipped with 15W (TDP) low-power processors, and the maximum power does not exceed 25W. discrete graphics card. The processors and graphics cards of game books generally start at 45W and 50W, and stronger performance will inevitably lead to more power consumption.

　　The second is the built-in battery capacity of the notebook. In order to slim down or reduce costs as much as possible, some notebooks will choose to sacrifice battery capacity, which will lead to a sharp drop in their battery life. In short, increasing the battery capacity is the only way to prolong the battery life of the notebook.

　　At present, the vast majority of notebook batteries use lithium polymer cells, which are a flat battery structure that is fixed in the notebook body by screws and cables.

　　If you remove the back cover of the notebook and carefully observe the surface of the notebook battery, you will see countless certification and parameter information, such as the mAh capacity unit that we are most familiar with.

　　In the field of smart phones, "mAh" is the standard unit of battery, and a mobile phone with a built-in 5000mAh capacity battery must have a longer standby time than a mobile phone with a 4000mAh capacity.

　　However, this common sense does not work in the field of notebooks, because the operating voltage of notebook batteries is not uniform, and it is necessary to use "Wh" to measure the actual energy of the battery, and the calculation formula of Wh is rated capacity (mAh) × rated work Voltage (V).

　　Taking the battery in the above figure as an example, its rated capacity is 7410mAh and its rated working voltage is 7.6V, so its actual energy is 7410mAh×7.6V, and the calculation result is 65.3Wh.

　　In fact, the actual energy of the mobile phone battery should also be counted in Wh, but because the rated operating voltage of the mobile phone battery is the standard 3.6V~3.8V, it can be directly divided into mAh. On the other hand, in the field of notebooks, the operating voltages of their batteries are mainly 7.5V, 11.5V and 15V, so it is meaningless to simply compare the unit of mAh. For example, a battery with a rated capacity of only 5550mAh can obtain 84.36Wh of energy at a rated voltage of 15.2V

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