This part is a kind of semiconductor called ICR18650-26A.

Function of this product has Lithium-Ion-Battery.

Manufacturers : Samsung

Image and pinout :

Some of the text within the PDF file :

-SAMSUNG SDI Confidential Proprietary – Spec. No. ICR18650-26A Version No. 1.0 SPECIFICATION OF PRODUCT for Lithium-ion Rechargeable Cell Model : ICR18650-26A January, 2005 Samsung SDI Co.,Ltd. Mobile Energy Division 0 -SAMSUNG SDI Confidential Proprietary – Spec. No. ICR18650-26A Version No. 1.0 1. Scope This product specification has been prepared to specify the rechargeable lithium-ion cell ('cell') to be supplied to the customer by Samsung SDI Co., Ltd. 2. Description and Model 2.1 Description 2.2 Model Cell (lithium-ion rechargeable cell) ICR18650-26A 3. Nominal Specifications Item 3.1 Nominal Capacity 3.2 Minimum Capacity 3.3 Charging Voltage 3.4 Nominal Voltage 3.5 Charging Method 3.6 Charging Current 3.7 Charging Time Spec [ ... ]

ICR18650-26A PDF Datasheet Download