Batteries are user-friendly under normal circumstances. Hence they should function seamlessly exactly as intended.However, they do contain corrosive chemicals that could harm us if we come in contact. Provided you follow these simple guidelines to make sure your battery is safe, you should be okay. Do remember this rule of thumb though. If your battery starts misbehaving, disconnect it.
Make Sure Your Battery is Safe by Storing It Correctly
You could store batteries almost anywhere you like in a dry place, provided the metal contacts do not start corroding. However, the ideal ambient temperature range is 50F to 85F. Batteries self-discharge faster outside this range. Avoid storing batteries below -4F because this may damage the electrolyte. Batteries feel the cold.
Always Charge Your Battery per Manufacturer Instructions

Only charge a battery from an external source at the correct voltage. Make sure your battery is safe while charging by double checking the charger settings. Alternatively use the transformer supplied with your device.
Connecting the terminals the wrong way round can lead to overheating. Avoid overcharging a battery. Never carry a loose battery in your pocket.
Protect Your Battery from Damage or Other Trauma

Never drop a battery to the ground, or use it as a hammer or a lever. Take care not to short the terminals by touching them with a metal object, tool, necklace, or steel watchstrap.
Because leaving a battery in this state could lead to overheating and possible thermal runaway. At the very least, you could ruin the battery.
Make Sure Your Battery is Safe by Keeping It Intact
Batteries produce electricity by means of electro-chemical reactions. If they bubble, bulge, change their shape, or smell odd, discard them. Never hit nails or screws through them, crush them in a vice, or throw them in a fire. Also, make sure your battery is safe after using it, by disposing it responsibly.
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Preview Image: Leaked Button Battery