Smart battery, what the mean is smart? Because it knows core. The appearance of the batteries has been over one hundreds years, the simple protection function can not satisfy the need of modern society. Nowadays, the high technical battery, the users need to know the reminding battery power, the reminding battery time,current voltage, current, temperature and other information.
As early as 20 years , battery fuel gauge IC was not yet available,the earliest design was stand-alone tablet through AD port to check battery voltage that judge the reminding battery power. But the method of voltage test was relatively accurate for small current discharge and the error of battery power. Because the voltage is gradually decreased. By setting several fixed voltage point to determine capacity, such as 100%,75%,50%,25% and 10%, the corresponding voltage could be used(as shown in figure one). However, if the large voltage is discharge,it is not suitable . Cause the large current discharge, the voltage fluctuations were relatively large. It was like the early mobile phones that displayed two bars of battery before making a call but had a low battery warning during the call (as shown in figure two). This caused misunderstanding for consumers, they will thought the problem was with the product and demanded refunded or exchanges. However, this was due to the lack of other available designs at the time and unstable battery materials.
With the advancement of technology, battery materials are becoming more and more stable, and battery management ICs are constantly emerging, innovating, and improving, with the most representative being international giants such as Texas Instruments and Maxim. Many high-end products in the market will use battery gauge ICs. What is a battery gauge? As the name suggests, it is used to calculate battery capacity and the remaining working time. The battery gauge IC integrates internal measurement algorithms, such as Coulomb counting, impedance tracking, Kalman filtering, and other algorithms. It can calculate how much capacity the battery has remaining and how long it can be used based on parameters such as current, voltage, temperature, and usage. Common battery gauge ICs include BQ27541, DS2781, DS2782, BQ40Z50, etc.
After status updated to 0e and learning is completed as shown in figure 3 and 4, a batch file is exported for batch use. After protecting and burning aging data, the battery assembly production requires aging testing and charging and discharging cabinets to determine the battery capacity. The entire production process is very complex, as not only is the price of the battery gauge IC ten times that of a normal protection IC, but the battery assemble process is more complicated. This is why the battery with communication capability are so expensive. However, the advantage of the high price is that the device can accurately obtain information such as the battery voltage, temperature, current, remaining capacity, and estimated remaining time, which can prevent losses caused by device shutdown.
The future trend for battery development is undoubtedly the inclusion of battery capacity meters. Across all industries, the goal is to maximize battery performance, whether it be for large-scale automotive batteries or smaller wearable devices. Accurately estimating remaining battery capacity and time is critical, as batteries have become an integral part of daily life. However, we have developed a condition known as "battery anxiety," which leaves us constantly worrying about whether our batteries will last, particularly when travelling or without access to a power source. We may even be unsure of when to charge the battery, or how much battery life remains. If we can accurately calculate and display battery information, we believe that this anxiety can be reduced.