It can stand by for 15 years without power on. I haven't heard of such a powerful mobile phone. But this is not impossible. A new mobile phone "economize No.1" developed by xpal energy company of the United States is said to have the biggest feature of using a new AA "power" lithium battery, which can stand for 15 years without power on, can be used for 2 months with power on, and can support continuous call for 10 hours. However, this is limited to the use of original batteries.
It uses all plastic design, simple shape, similar to the remote control, the upper part of the screen similar to the location of the visible battery. In the middle of the upper part of the keyboard is a red emergency call key, next to which are four function keys, and the lower part is a number key, etc.
The mobile phone has no screen, no phone book, only supports digital input, excluding any power consumption miscellaneous items such as camera, Internet, etc. However, in order to make it convenient for users to make calls, the manufacturer has preset 9 groups of quick call numbers. The red emergency call key can also be called without a SIM card. Mobile phones are available to us users as well as European, African and most Asian users.