- What is a micro battery/button cell?
A "button cell" should actually be better called a "button battery", because it has the external attributes of a battery (further information) . Its popular name, however, is "button cell". A button cell may be defined as a battery whose diameter is equal to or larger than its height. Present dimensional limits for button cells using an aqueous electrolyte range from a) diameter: 4.8 mm to 11.4 mm, b) height: 1.05 mm to 5.4 mm. Depending on the electrochemical system their nominal voltage is either 1.2V, 1.35V, 1.4V, 1.5V or 1.55V. Batteries of this family were given this name because of their visual similarity to buttons. Coin Cells also belong to the group of button cells (further information).
- What are "dry" and what are "liquid" batteries?
The terms "dry battery" and "liquid battery" are restricted to primary systems and date from the early development of galvanic elements. At that time, a liquid cell consisted of an electrolyte-filled glass container into which electrochemically active electrodes were immersed. It was only later that unspillable cells which could be used in any position and had a completely different construction were introduced, these being similar to today's primary batteries. These earlier cells were based on paste electrolytes. At that time they were known as dry batteries. In this sense today's primary batteries are also dry batteries.
The term "liquid battery" is in principle still applicable to certain modern secondary batteries. For large stationary lead-acid or solar batteries, liquid sulfuric acid is preferred for the electrolyte. For mobile applications unspillable, maintenance-free lead-acid batteries are recommended and have been available for many years. Their sulfuric acid is immobilized by a gel (or a special microglass mat).
- Which type battery can be used in remote control devices?
The battery stipulated in its battery compartment should only operate a remote control device. Different zinc-carbon batteries are available for different remote control devices. They can be identified by their IEC designation. Commonly used batteries include the R03 (AAA, "Micro"), R6 (AA, "Mignon") and the 9V Block 6F22. A better choice is the alkaline versions of these batteries which offer twice the operating time of the zinc-carbon battery. They can be identified by their IEC designations LR03, LR6 and 6LR61. Nevertheless, because of the relatively low current required by this application, zinc-carbon batteries still remain a good and economical alternative.
Interchangeable accumulators may - in principle - be used as well. They are, however, less recommendable for this application because of their relatively high self-discharge, which requires repeated charging, thus rendering this type of battery rather impractical.