IEEE Consumer Electronics Magazine - September 2018 - 50

Energy and Security

Supercapacitors Outperform
Conventional Batteries
By Aditya Sankar Sengupta, Sambit Satpathy, Saraju P. Mohanty,
Debasis Baral, and Bidyut K. Bhattacharyya

or all present-day consumer electronic (CE) products, especially
those operating on dc voltage or
power, supercapacitors or supercapacitor modules may replace these
products' batteries in the near future,
eliminating batteries and all of the shortcomings associated with their technology. Because these CE products require
a constant dc voltage for operation, a
state-of-the art dc-dc converter module
operating solely on supercapacitors
without a battery is envisioned. A proposed dc-dc converter module would
deliver the required constant voltage to
the CE devices from the supercapacitors
corresponding to the dropping or decaying voltage of the supercapacitors or
supercapacitor module.
This is the first time in circuit design
where all electronic components will
run properly only on the power drawn
from the supercapacitors and generate a
constant voltage from the supercapacitors even though the voltage is dropping. The unique design will boost the
use of supercapacitors for all CE systems and products.

THE FUTURE POWER SOURCE
CE systems, e.g., laptops and mobile
phones, have become a part of our dayto-day life with modern era advancements in technology. CE electronic
systems and handheld devices, including
Digital Object Identifier 10.1109/MCE.2018.2835958
Date of publication: 9 August 2018

50 IEEE Consumer Electronics Magazine

This is the first time in
circuit design where all
electronic components will
run properly only on the
power drawn from the
supercapacitors.
camcorders, tablets, and mobile phones,
use batteries for energy storage. With the
enhancement in the specification of these
devices, high-capacity batteries (e.g., lithium-ion) are required. These batteries take
longer to charge and discharge comparatively faster to meet the power requirement for high-specification CE devices.
To deal with these issues, the concept
of using supercapacitor technology in
place of batteries was proposed. As an
alternate source of power storage and
supply, supercapacitors have brought
new possibilities in technology. Since
the equivalent series resistance is significantly less compared to the internal
resistance of batteries, supercapacitors
charge much faster than batteries [1],
[2]. Figure 1(a) shows modern, diverse
applications where supercapacitors are
used, while Figure 1(b) shows a supercapacitor-based hybrid vehicle where a
dc-dc converter is used with a supercapacitor and battery.
An invention of material science,
supercapacitors have been deemed the
future of energy storage and power supply in the field of power engineering and

september 2018

industrial electronics. This article demonstrates a unique and novel analog buck
circuit design that is powered solely by
supercapacitors. This prototype was designed to eventually replace batteries in
future CE devices when supercapacitors
are miniaturized, which is a task that
researchers around the world are working
to achieve. This article is the first work
where a circuit powered solely by supercapacitors and devoid of any other power
source is being shown, and it is the first
step toward batteryless CE systems.

SUPERCAPACITORS
VERSUS BATTERIES
Supercapacitors have a number of advantages over batteries; the most important is the charging time, which is much
less for supercapacitors as compared to
batteries [3], [4]. Supercapacitors are
hazard free, unlike batteries [5], which
are prone to explosion. Supercapacitors
also have a much longer life cycle compared to batteries [4], [5], and a very
high power density [6] that allows a
high amount of power to be pumped in
a short amount of time.
Figure 2 shows the power drawn by
supercapacitors versus that drawn by the
battery applications as a function of current drawn by the devices; the green
curve is the power consumed by the battery due to its own equivalent series
resistance, while the blue curve is the
power consumed by the supercapacitors.
The black, dashed line shows that if the
power is too high, then a battery may

Table of Contents for the Digital Edition of IEEE Consumer Electronics Magazine - September 2018