Do not know if you are also encountered the same problem with me, Thinkpad s220 laptop power, the machine can not detect the laptop battery, the battery is not available, and this is how is it?

       Based on the information I learned online, this situation is mainly caused by the following three kinds of problems.

       Question 1: It may be that the ThinkPad s220 you use is undervoltage protection after the notebook battery is undervoltage, the FET is not activated and the battery data transmission fails, there is no communication. Currently there is no communication protocol except the Toshiba battery. The battery has a communication protocol, and communication is about whether the battery information can be recognized by the computer.

       Solution: If the conditions permit, it can be loaded with forward current of -100mA at both ends of the battery.

       Question 2: The battery enters other protection status, and the battery caused by the flag bit position enters the protection state. In this case, the battery charging and discharging FET will be turned off. The battery will show no output and the input status will cause the computer to fail to detect the battery.

       Solution: Return to factory maintenance, software flag position or hardware shutdown all require professionals to solve.

       Question 3: The pin ID of the battery output terminal defines an open circuit (usually oxidation or poor contact) with the ID pin between the computers. I believe your battery must have been used before.

       Solution: You can use a small tool blade with a grinded surface to gently grind the notebook battery's plug hardware and the computer's contacts, or buy a new battery.