have been widely used in aviation industry since the beginning of plane
history. During earlier age of aviation, electricity was mostly used to ignite
the airplanes engine. As technology progress, more advanced airplanes and jet are
developed and equipped with a sophisticated electrical system. While engines
able to serve as generator and provide electricity, batteries are required to
provide electricity before the engine started and serve as a part of ignition system
in the engine. This battery also serves as backup power in the event of engine
failure. Battery used for these purposes are called main battery. In most of
the advanced airplanes, another battery usually installed to serve as auxiliary
power unit (APU).
in batteries operation is converting chemical energy to the electrical energy.
This process occurs through electrochemical discharge of the reactant. However,
they are limited time in converting this energy since reactant can be depleted
and unable to supply electron. Batteries
that unable to restore their reactant are called primary batteries. Some of the
batteries have the capability to restore their reactant to its initial state by
charging it through direct current. These batteries are called secondary batteries.
In airplanes, secondary batteries are widely used as it able to be used
multiple time through a cycle process of charge and discharge.
chemistry of the battery used in airplanes are usually lead acid, nickel cadmium
or lithium. The battery used are big in nature since its consisted of multiple
cells connected in a series-parallel connection to give desired operation
requirement. Batteries are rated based on their nominal voltage and capacity.
Battery with 1000mAh capacity will have a runtime of 1 hour before completely
discharge when discharge with 1A. This discharge rate is equivalent to 1C. Subjecting
battery to a discharge rate of 2C means battery are discharge with 2A and will
have a runtime of 30 minutes before it is completely discharge. High rate cell can
be achieved by minimizing the internal resistance of the cell which highly
dependent on the internal construction of the cell itself.
use of lithium ion battery in aviation is quite popular due to energy density
that it can offer. Higher energy density means, more power can be supplied with
a smaller battery. Space required for battery installation is small as some of
the battery size can be similar to the size of car battery. Total weight of the
aircraft can be reduced leading to reduce in airplanes fuel consumption. Lithium
ion battery also have excellent life cycle, faster recharge time and require minimal
maintenance compared to nickel-cadmium battery. Boeing, an airplanes manufacturing
company have been knowingly used lithium ion battery in their airplanes, B787.
However, due to accident of thermal runaway of the B787 battery in 2013, concern
regarding the safety of using lithium ion battery in aviation arises, making
Airbus to drop the use of lithium ion in their A350 fleet. Immature technology
of lithium ion lead to further development in minimizing the risk of thermal
runaway in battery as year progress. Saft, a battery-maker company has succeeded
in developing more stable lithium-ion battery, making Airbus to deliver their first
A350 equipped with lithium ion battery in 2016.