Avionics News February 2021 - 36

A BATTERY OF OPTIONS
Continued from page 35

the Airbus H135, Leonardo 109 and Bell 407 Series helicopters
are in development. "
As of this writing in mid-December 2020, 16 STCs were
available or pending for a wide variety of applications using
True Blue Power batteries.
Among the aircraft approved are the Robinson R44
helicopter; Beech King Air 350 and A36 Bonanza; Pilatus
PC-12, PC-12/45, PC-12/47; MD Helicopters MD 500; de
Havilland DHC-8 Dash 8 (100, 200 and 300 variants); de
Havilland DHC-6 Twin Otter (100, 200 and 300 variants);
Cessna Caravan 208 and 208B; Boeing 737; Bell Helicopters
206 and 429, both pending; and Airbus Helicopters H125,
AS350, EC130 B4 and EC130 T2, pending approval, the
Airbus Helicopters EC135 and H135, EC145 and H145.
True Blue Power's battery lineup has in recent years
expanded significantly from the original TB17 and TB44,
with the addition of the TB20, TB30, TB40, and TB60.
True Blue Power also offers matching components
designed to work with its products. Among them, USB
charging ports, marine USB charging ports, emergency
power supplies using the same lithium-ion chemistry, battery
testers, chargers and conditioners, connector kits and the
MD41-1844 Annunciation Control Unit for the avionics
stack. The fully integrated control unit provides annunciation
for the TB44 battery system's ACU. It combines the
necessary functions and annunciations required to interface
with an approved system.
For those who prefer other
battery technologies
Concorde Battery Corp. is a longtime supplier to the
aviation market as well as for marine, solar, and wheelchair
needs. Concorde manufactures specialty absorbent glass
mat aircraft batteries and is the leading producer of AGM
batteries as well as a variety of industrial AGM batteries for
deep cycle use and for engine-starting use.
But Concorde isn't ignoring the potential of lithiumion batteries for aircraft applications. Concorde's new
in-development lithium-ion batteries will employ one
of the safest chemistries available, featuring a cathode
material made of lithium iron phosphate, which is more
stable than oxide-based cathodes. The batteries include a
microprocessor-based battery monitoring system to monitor
individual cell activity and protect the battery from abnormal
conditions.
In general, Concorde's lithium-ion aircraft batteries will
not be a retrofit battery due to the integration of the BMS. In
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2021

order to assure safe operation, the lithium-ion battery needs
to be incorporated into the software and electronics of the
aircraft system.
Redundant safety systems built into the aircraft as well as
into the battery are generally required to monitor and control
the battery during all foreseeable conditions.
The U.S. Navy also selected Concorde's lithium-ion
battery technology for the CH-53K helicopter for its high
energy density, low maintenance, ease of use, and low
self-discharge. CH-53K is slated to be the new heavy lift
helicopter, part of the Navy's Heavy Lift Replacement
program.
Additionally, Gill Batteries offers a wide selection
of sealed lead-acid batteries for a variety of aircraft
applications.
NiCad
Nickel-cadmium cells employ a cadmium hydroxide
anode with a nickel-hydroxide cathode, with both immersed
in an electrolyte made up of potassium, sodium and lithium
hydroxides. Nickel-cadmium batteries require relatively low
maintenance, are reliable and have a wide operating temperature
range. Downsides include NiCad batteries being subject to the
memory effect and the potential for thermal runaway when
overcharged. Additionally, many nations enforce strict disposal
regulations on NiCad batteries because of the heavy metals
they contain. NiCad batteries are suitable for many aircraft
applications inclusive of main aircraft batteries.
Nickel-metal hydride
Nickel-metal hydride cells employ an anode of a metal alloy
capable of absorbing and releasing hydrogen. The cathode
consists of nickel hydroxide. Both substances are immersed
in an electrolyte solution of potassium, sodium and lithium
hydroxides. Small capacity cells of this type of battery are
sealed and are maintenance free. Their principal shortcoming
is that they require precise charge level monitoring to control
gaseous exchanges and to minimize heating while under charge.
Ni-MH batteries have a high energy density and are ideal for
high-capacity requirements. In aircraft, Ni-MH batteries are
often used to power systems such as the emergency door and
floor escape path lighting as well as portable entertainment
devices and electronic flight bags.
Lead-acid wet cell
Still the dominant battery technology, thanks to absorbent
glass-mat and sealed gas recycling batteries available for a
wide variety of aircraft applications. Wet-cell batteries are a
known technology, and the newer versions require virtually no
maintenance between annual checks. q

Avionics News February 2021

Table of Contents for the Digital Edition of Avionics News February 2021