9V batteries are intended for smoke alarms, and are not suitable for Arduino projects.For very low power battery operated projects, special techniques are required. Study this excellent tutorial for the details.
Is it a 9v battery like you would use in a smoke detector?Those work for smoke detectors and transistor radios that pull almost zero amps.But in an application where more current is needed, they are virtually useless.Look at the datasheets for your components to see what current they require.Choose a suitable power supply.
To be a bit more constructive, small 9V alkaline batteries are probably good to 50mA or so beforegross-overload sets in - check the voltage if it falls significantly below 9V, its grossly overloaded!Rechargable 9V batteries may provide more current, but are usually only 8.4V nominal, its always good if you find the datasheet for a battery (which means avoid unbranded batteries, basically, theyare usually pretty rubbish capacity anyway)For small energy-dense batteries nothing really competes with lithium chemistries, although LiPorequires precautions due to the fire hazard. LiFePO4 seem a good compromise, less fire risk, largenumber of charge/discharge cycles. You can find 6.4V and 9.6V LiFePO4 packs for RC models, usuallysold as "receiver packs", for instance.
to get the battery of my program running for 6- 8 month
I understand but the fact so,how and why i supossed to do, to get the battery of my program running for 6- 8 month when i used the arduino I2lcd with Arduino Pro Mini 328.
Look at the datasheets for your components to see what current they require.Choose a suitable power supply.
This was covered up in reply #2.So, go dig up the datasheets for your components. Add up their current requirements.If you do not have those data sheets, you can put an ammeter between the battery and your device and measure the current draw. I have a watt meter that tells me the current. That would work too.Choose a battery with enough capacity to provide that power for 8 months.Example: You calculate a 100mA total current requirement from the datasheets. That will consume 100mAh in one hour. There are 5760 hours in 8 months. You will consume 576Ah in 8 months.Choose a battery with that capacity.
If you want micropower(*) operation the Uno is definitely not the board to use as its not micropower andcannot be configured as such because the USB interface takes constant power whether or not themicrocontroller is in sleep.Something like a bare bones board or a board designed for micropower is needed.http://www.home-automation-community.com/arduino-low-power-how-to-run-atmega328p-for-a-year-on-coin-cell-battery/(*) micropower means very low power (microwatts on average), allowing for unattended battery operation.