With the progress of science and technology and the rapid development of domestic construction, in recent years, intelligent flow meter (e.g., intelligent gas meter, water meter, heat supply tables, compound rate meter, intelligent flow meter used in industry, etc.) of the growing market demand, in the r&d and production of intelligent flow meter, choose safe and reliable power supply for instrument, has become an important topic.

Choose intelligent instrument power mainly has three aspects:
1, can continuously provide enough power for normal operation of the instrument;
2, the use of safe;
3, free maintenance for a long time. Using mains, cannot guarantee power, and is used for gas meter, water meter, such as poor safety, so the batteries are used as the instrument power supply. Use rechargeable batteries, not solve the problem of connected to mains.