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Battery Information
Battery Details

The Lithium Thyonyl Chloride 2/3A can replace the CR123 in low current situations but should NEVER be used for cameras.
The CR123 can replace 2/3A Lithium Thyonyl Chloride (LiSocl2), where the extra .6 of a volt is non critical, the CR123 lasting longer.

About the Chemistry:

NOTE: These Lithium types are NOT rechargeable, they are single use batteries.

• Lithium Manganese Dioxide (LiMnO2) suitable for high current drain e.g. torches and radio control uses.
  
  
• Lithium Thionyl Chloride (LiSocl2) suitable for low drain e.g. memory back-up, smoke detectors etc.
  
  Some Lithium Thionyl Chloride (LiSocl2) are "Spiral Wound" construction and are suited to high current drain (designated by the suffix "M", i.e. ER*****M).
  You can use any of the high drain types to replace a low drain LiSocl2 but don't try to replace the high drain types with a low drain LiSocl2 or explosion due to overheating could occur.

Equivalents:

123, 123A, 23-155, 5018LC, BA-5123, BR-2/3A, Camera Battery, CR123, CR123A, CR-123, CR-123APA, CR-123AW/2BE, CR17335, CR17335SE, CR17354, CR23, DL123, DL123A, DL123A-1, DL123A2, DL123A-2, DL2/3A, EL123, EL123A, EL123AP, EL123AP-2, EL123APBP, ER2/3A, K123A, K123LA, KL123LA, L123A, LR123, PR123A, RCR-123A, RL123, RL123A, RL123A-1, RL123A-2, SF12-BB, SF123, SF123A, T32/51, V123, VL123, VL123A,

Image not to scale.	Common Name.	Dimensions. Length × Diameter.	Chemical Composition.	Nominal Voltage.
	123.	34.5 mm × 17.1 mm Contacts: Raised "pip" Positive. Flat end Negative.	Lithium,	3 volts. 1300 mAh