Mobile power internal lithium battery detection scheme

Source: 2020 - 04 - 14 and clicks: mobile power internal lithium battery detection scheme with the emergence of large capacity, energy intensive mobile electronic products, mobile backup power supply has been developed. Mobile power charging commonly known as the treasure, is insufficient to make up for the mobile electronic product itself battery and conceived. Energy-intensive electronic products like iPhone. Mobile power itself is composed of large capacity lithium battery and internal control circuit. Control circuit is divided into two kinds, a kind of simple improving combined control chip and MCU, the other for special charging control chip formation, booster, over current, over voltage and short circuit protection of integrated circuit system and the solution is to reduce the cost, control more complete, the advantages of the system more secure, more and more consumers. In the mobile power supply all kinds of special control chip of the control system, has an important control links, namely the mobile power supply power indicator of the internal lithium battery. Mobile power supply 1. Circulation of electric power consumption display method at present, the general scheme of display mode is based on four LED lights for the mainstream, so this paper also USES four LED lights display mode to illustrate. In general, it is the total power of the mobile power supply is divided into four parts: 25%, 50%, 75% and 100%. Show four leds, respectively. The earliest power indicator is basically through mobile power battery voltage to divide power size. Such as the battery voltage is divided into 3. 3 V, 3。 6 V, 3。 9 V, 4。 2 V, divided into 25%, 50%, 75%, 100%, when the battery voltage is 4. 2 V ~ 3。 9 V battery 100% of the total power battery, 3 when the battery voltage. 9 V to 3. 75% of the total of 6 V battery of battery, the battery voltage is 3. 9 V ~ 3。 50% of the total power battery 6 V battery, 3 when the battery voltage. 6 V to 3. 3 V battery for 25% of the total power. 2. With internal resistance compensation power detection scheme for further solution, battery voltage reference at the same time, synchronous acquisition battery current, according to the size of the current collection to calculate equivalent of battery internal resistance ( Including the line resistance and protection of integrated circuit switch conduction resistance) , then the additional internal resistance pressure drop of the reference voltage, battery capacity, will help to improve the detection accuracy of battery, further way of measurement. But after the improvement, the scheme also has certain problem. Hard to different battery capacity and mobile power supply manufacturer, to ensure that the equivalent resistance is an effective compensation, it is necessary to adjust the compensation value in each batch, which means a special adjustment of the needle also need to control resistance compensation control chip. In addition, these two reference threshold scheme is battery charging and discharging inconsistent problem. So, charging and booster judgment reference voltage is different, can lead to recharge and booster transfers, the different status of the remaining power. Charging for example, found that 75% of electricity, showed that 50% of electricity is converted to increase output. Of course, this is caused by battery charge and discharge curves are different. Think at present, the battery better way is to use battery meter chips. Voltmeter chip design is more complex, however, the voltmeter circuit design to join in the cost of production of mobile power supply is not easy, it requires MCU, a large number of digital processing, complex algorithm. This paper proposes a don't need too complicated digital circuit, but it can improve the battery life test method.