A battery is a chemical product which produces electricity by chemical reactions at its inside. These reactions and its inside materials do deteriorate over time.

A hot battery could have several causes: from wrong storage to short circuiting. Some warmth is okay but keep an eye out for unusual heat.

Yes. All batteries have an expiration date, beyond which their performance decreases.

This should be avoided at any time. When the battery has been in a washing machine, it is no longer fit to use. Please dispose of this battery.

Alkaline batteries cannot be recharged.

Immediately head to the nearest emergency room. Avoid drinking or eating before a doctor has provided a decent diagnosis.

Due to chemical reactions inside most batteries, the stored charge of the batteries is reduced little by little. This phenomenon is called self-discharge.

Make sure you measure the correct way: connect the poles to their corresponding measuring ends.

The revised RoHS (Reduction of Hazardous Substances) Directive 2011/65/EU...

In case of skin contact there is a chance of chemical burns. Use clear tepid water for at least 15 minutes on exposed skin. Consult a physician in case of irritation, injury or pain. In case of contact with the eye, do not rub the eyes, but flush with clear tepid water for at least 30 minutes.