Which is company provide battery?

all we can say is that all iphone battery was made in china... :)

btw, here's the company list that manufactured iPhone's part (according to reuter data) :

According to Reuters, Jyly 2, 2007

Following are some of the key parts and their makers that have been identified so far:

1. South Korea's Samsung Electronics Co. Ltd. (005930.KS: Quote, Profile, Research) makes the main processor as well as the flash memory chips that store music, photos and other user data *

2. The processor is based on an architecture licensed from Britain's ARM Holdings Plc (ARM.L: Quote, Profile, Research) #

3. Germany's Infineon Technologies (IFXGn.DE: Quote, Profile, Research) supplies the phone's transceiver and baseband processor #

4. Britain's Wolfson Microelectronics Plc (WLF.L: Quote, Profile, Research) makes the audio processing chip. Wolfson already supplies audio chips for Apple's popular iPods *

5. U.S.-based Marvell Technology Group Ltd. (MRVL.O: Quote, Profile, Research) makes the Wi-Fi chip that allows the iPhone to connect to the Internet wirelessly *

6. Skyworks Solutions Inc. (SWKS.O: Quote, Profile, Research) supplies the cellular network power amplifier *

7. Britain's CSR Plc (CSR.L: Quote, Profile, Research) makes the Bluetooth chip that supports wireless accessories such as microphones *

8. Linear Technology Corp. (LLTC.O: Quote, Profile, Research) supplies the USB battery charger, a part that is also used in iPods #

9. Broadcom Corp. (BRCM.O: Quote, Profile, Research), privately held NXP Semiconductors and National Semiconductor Inc. (NSM.N: Quote, Profile, Research) make components to support the touch screen #

10. Micron Technology Inc. (MU.N: Quote, Profile, Research) makes the 2-megapixel image sensor for the iPhone's camera #

11.Other components were supplied by Texas Instruments Inc. (TXN.N: Quote, Profile, Research), Europe's STMicroelectronics (STM.PA: Quote, Profile, Research), Silicon Storage Technology Inc. (SSTI.O: Quote, Profile, Research) and RF Microdevices Inc. (RFMD.O: Quote, Profile, Research)