Yuasa CR2 3V Lithium Battery, 1000mAh 1CR2

Overview

CR2 is a standard cell name rather than a brand of its own. It tells you the shape and the chemistry family, so the name on your old battery is the first thing to check.

Where to use it

CR2 cells often turn up in cameras and compact sensors. Check the marking on the device or its old cell before you order.

When replacing alarm batteries, follow the device maker's instructions, because some systems need a walk test or a tamper reset afterwards.

What the figures mean in practice

• mAh: milliamp hours, a measure of stored charge. 1000mAh is the nominal figure, so a heavy or very cold load gets less from the cell.
• 20mA: the load the maker rates it at. Voltage holds up differently at other loads and temperatures.

Installing it

• Polarity: the raised end is the positive terminal. Match it to the marks in the holder.
• Handling: keep spare cells apart so their ends cannot touch metal, and never try to open or heat one.
• Disposal: take used cells to a battery collection point rather than household waste.

Planning your system

A device with several cells usually needs all of them replaced together. Other specialist batteries are worth stocking if your site uses more than one size, and date a new cell so the next change is easy to plan.