This part is a kind of semiconductor called INR18650-25R.

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. INR18650-25R Version No. 1.0 In-Young Jang SPECIFICATION OF PRODUCT Lithium-ion rechargeable cell for power tools Model name : INR18650-25R Mar., 2014 Samsung SDI Co., Ltd. Energy Business Division -SAMSUNG SDI Confidential Proprietary – Spec. No. INR18650-25R Version No. 1.0 In-Young Jang Contents 1.0. Scope 2.0. Description and model name 2.1. Description 2.2. Model name 3.0. Nominal specification 4.0. Outline dimensions 5.0. Appearance 6.0. Standard test conditions 6.1. Environmental conditions 6.2. Measuring equipments 7.0. Characteristics 7.1. Standard charge 7.2. Rapid charge 7.3 Nominal discharge capacity 7.4. Standard rated discharge capacity 7.5. Initial internal impedance 7.6. Temperature dependence of discharge capac [ ... ]

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