Layer cell for portable power 

Layer cell design as a portable power source is very economical for low drain devices like FM radios where the current drain requirement is less than 30mA.

In the layer cell construction, a duplex electrode is formed by coating a zinc plate with a carbon filled conductive paint. This coating performs the following functions:

• provides the electrical contact to the zinc anode
• isolates the zinc from cathode of the next cell
• Performs the function of cathode collector.

The flat cell design increases the available space for the cathode mix because the package and electrical contacts are minimized thereby increasing the energy density. Also, rectangular construction reduces wasted space in multi-cell assemblies. Hence, Layer cell batteries are the most preferred for multi-cell construction used in low drain devices.

The volumetric energy density of an assembled battery using layer cells is nearly twice that of cylindrical cell assemblies.

The advantages of layer stack batteries for low drain devices are

• High energy density by design means more capacity
• No extra components like carbon rods, jacket, etc. & hence cheaper
• Compact in size due to efficient utilization of space
• Value for money in low drain devices like FM radio, LED lighting, Alarms, monitoring systems etc.