Testers for Modern Batteries for Mobile Devices
President, Cadex Electronics Inc. firstname.lastname@example.org
Rechargeable batteries are known to
cause more concern, grief and frustration than any other part of a
portable device. Given its relatively short life span, the battery
is also the most expensive and least reliable component.
How are batteries checked and
serviced? This article describes the advancements of the modern
battery analyzer and how these instruments are used in industry.
While organizations such as public safety have been using battery
analyzers for many decades to restore and prolong nickel-cadmium
batteries, battery analyzers are beginning to make their way into
the mobile phone market. Early models were impractical and did not
adapt to the rapidly changing pool of batteries. In addition, the
analyzers were complex and did not offer the quick and accurate
service customers demanded.
The last few years have brought a
rebirth in battery analyzer technology. Gone are the units that do
nothing more than cycle batteries. With the move from
high-maintenance nickel-based batteries to lithium-based batteries
that no longer require periodic discharges, the duty of a battery
analyzer is changing from extending battery life to quick testing
and quick fixing.
There are two basic types of battery
analyzers: fixed current and programmable. While fixed current units
are less expensive and generally simpler to operate, programmable
analyzers are more accurate and faster. Programmable units allow
better adaptation to different battery needs and are more effective
in restoring weak batteries. The ability to quick test batteries is
reserved for the programmable units only.
From a technical point of view, the
two analyzers function as follows: Inserting a battery into a fixed
current device commences service at a fixed charge and discharge
current of about 600mA. Smaller batteries get serviced reasonably
fast but larger batteries are slow. The service time of an 1800mAh
battery is three times that of a 600mAh pack. The capacity readout
is in mAh and reflects the length of discharge. In comparison, the
programmable units service the battery against preset parameters.
The readout is usually in percentage of the nominal battery
The programmable battery analyzer
The programmable battery analyzer
retains battery settings and test parameters in the system, commonly
in the battery adapters. This allows batteries to be serviced to
manufacturer’s specified settings. Figure 1 illustrates a
programmable battery analyzer.
Battery-specific adapters are
available for all major batteries. User-programmable cables with
alligator clips accommodate batteries when no adapter is on hand.
For service centers, a universal battery adapter eliminates the need
for custom adapters. Two contact probes mounted on flexible arms
provide the connection when they are lowered to the battery
terminals. Magnetic guides keep the battery in position.
1: Cadex 7400 battery analyzer
The Cadex 7400 services nickel,
lead and lithium-based batteries. The analyzer is programmable
to a wide range of voltage and current settings. Custom
battery adapters simplify the interface of different battery
types. The Quicktest™ program measures battery
state-of-health in three minutes, independent of charge.
Nickel-based batteries are automatically restored if the
capacity falls below the user-defined target capacity.
Advanced battery analyzers are
capable of evaluating battery condition and implementing corrective
service to restore performance. On nickel-based systems, a
recondition cycle is applied automatically if a user-selected target
capacity cannot be reached.
User-selectable programs service
different battery needs. On the Cadex 7000 Series for
example, Prime prepares a new battery for field use and Auto
tests and reconditions weak batteries. Custom allows the
setting of unique cycles composed of charge, discharge, recondition,
trickle charge or any combination, including rest periods and
Advanced battery analyzers are
capable of measuring internal battery resistance. Obtained in a few
seconds, resistance readings work well with lithium-based batteries
because the cell resistance is in direct relationship to
performance. Internal resistance readings can also be used for
nickel-based batteries, however, the results do not accurately
disclose the battery’s state-of-health.
To increase precision, advanced
battery analyzers offer quick test programs. The Cadex Quicktest™
works using artificial intelligence algorithms, which adapt to new
battery types through learn cycles. The more learn cycles
from batteries with varying capacities are completed, the more
accurate the readings will be. Learn matrices are stored in the
battery adapters and are added at time of manufacturing.
The Cadex Quicktest™ is
performed with battery charge levels of 20 to 90 percent.
If outside this range, the analyzer automatically applies a brief
charge or discharge to bring the battery within testing range. The
test lasts three minutes, longer if preparation is needed. The
charge level does not affect the reading.
Batteries are often discarded, even
when restoration is possible. Mobile phone dealers have confirmed
that 80 to 90 percent of returned mobile phone batteries can be
repaired with a battery analyzer. But most dealers are not equipped
to handle the influx of batteries returned under warranty. They are
sent back to the manufacturers or are discarded without attempting
to restore them.
To better serve the needs of the
mobile phone industry, advanced battery analyzers include quick fix
programs consisting of ultra-fast charging and power boosting. For
example, Cadex Boost is able to wake up Li-ion batteries that
have become unserviceable due to very low discharge. The program
applies a gentle charge to activate the protection circuit and raise
the voltage to operation levels.
Unlike the even current flow
reminiscent of analog devices, digital equipment loads the battery
with hefty current bursts. The Global System for Mobile
Communications (GSM) transmits voice data in 567 m s bursts
with pulse currents of 1.5 amperes and higher.
Modern battery analyzers are capable
of simulating digital loads, allowing battery testing under field
conditions. It should be noted, however, that not all analyzers are
capable of reproducing the short GSM current bursts. Medium-priced
units often use lower frequencies. The capacity readings are
slightly higher when discharged at lower frequencies than in real
time. A simulated pulse discharge, even if done at lower
frequencies, provides more accurate readings than direct current
Most analyzers print service reports
and battery labels. This feature simplifies maintenance, especially
in a fleet environment where operators must observe periodic service
requirements. Labeling batteries with the last service date reminds
the user when the next service is due. Labeling works well because
the basic service history is available where it is needed most —
on the battery.
Some battery analyzers are available
with software for PC interface. This option expands the
functionality of battery analyzers, simplifies operation and allows
users to perform complex and accurate battery tests with minimal
training. In addition, PC software enables design engineers to
collect and store valuable battery information by running customized
Cadex Batteryshop™ is a
Widows-based software that works in conjunction with Cadex 7000
Series battery analyzers. Although the analyzers are stand-alone
units, the software overrides the analyzers when connected to a PC.
To service a battery, the user selects the battery model from the
database and clicks the mouse. The PC configures the analyzer to the
correct parameters, ready to service the battery. Programming the
analyzer by scanning the battery model is also possible.
Fleet batteries are serviced by first
marking all packs with a unique battery ID number. Batteryshop™
generates these labels in bar code format. The user scans the
battery ID and the analyzer is automatically programmed to the
correct battery setting through the PC. All battery test results are
stored and updated in the database under the assigned battery ID
number. Any reference to the battery in terms of performance,
maintenance history and vendor information is available with a click
of the mouse. This feature enables retaining battery records from
birth to retirement.
also assists battery manufacturers and pack assemblers. Among
typical applications are: life cycle testing, batch checking for
quality control and documenting warranty claims. Chemistry, voltage
and current setting are entered manually through the PC. Charge,
discharge and temperature curves can be displayed in real-time
The Internet is poised to play a
pivotal role in battery testing. Batteryshop™ will be able
to fetch matrices for quick test measurements, send battery test
results to a central location, and download firmware to upgrade
existing equipment. The software is equally proficient supporting
one analyzer or a fully extended system of 120 units.
Battery analyzers have found two
distinct market applications: first to maintain and restore fleet
batteries for established battery users such as the public service
sector, and second to check and repair personal batteries used in
mobile phone and related markets. The second application requires a
more complex model because of the large variety of batteries in
circulation and the diversity of user groups.
Manufacturers of battery analyzers
are experimenting with new ideas to simplify battery testing. Proven
models from other industries are being evaluated. One such model is
the automated checkout system of a supermarket. Here, the clerk is
relieved of memorizing detailed product information to complete the
transaction. This knowledge is embedding in the system.
Up-to-the-second inventory status is available at any time.
Embedded systems will also help to
streamline battery testing. This is especially pertinent for larger
service centers and businesses that operate internationally. The
task of global training is simplified when complex functions and
procedures can be included in a user-friendly package. Retaining
test results at a central location is another benefit such a system
Reference: This article
contains excerpts from the second edition book entitled Batteries in
a Portable World — A Handbook on Rechargeable Batteries for
Non-Engineers. In the book, Mr. Buchmann evaluates batteries in
everyday use and explains their strengths and weaknesses in laymen’s
terms. The 300-page book is available from Cadex Electronics Inc.
through email@example.com, tel.
604-231-7777 or bookstores. For additional information on battery
technology visit www.buchmann.ca.
About the Author
Isidor Buchmann is the
founder and CEO of Cadex Electronics Inc., in Richmond (Vancouver)
British Columbia, Canada. Mr. Buchmann has a background in radio
communications and has studied the behavior of rechargeable
batteries in practical, everyday applications for two decades. The
author of many articles and books on battery maintenance technology,
Mr. Buchmann is a well-known speaker who has delivered technical
papers and presentations at seminars and conferences around the
About the Company
Cadex Electronics Inc. is a world leader in the design and
manufacture of advanced battery analyzers and chargers. Their
award-winning products are used to prolong battery life in wireless
communications, emergency services, mobile computing, avionics,
biomedical, broadcasting and defense. Cadex products are sold in
over 100 countries.