AN-1052 Datasheet, PDF (1/10 Pages) Cymbet Corporation – Operating the EnerChip in High Temperature Environments

AN-1052
Application Note
Operating the EnerChip™ in High Temperature Environments
Introduction
EnerChip™ solid state rechargeable batteries are distinct from conventional rechargeable batteries. The
EnerChip can be used in environments typically ill-suited for batteries and other storage devices at risk of
leaking toxic and volatile solvents, catching fire, exploding in high temperature environments, or that are simply
too large to fit within space-constrained enclosures. The EnerChip CC combines the EnerChip with integrated
power management, for use in applications requiring backup or bridging power, or as the main power source.
Some applications demand occasional operation at temperatures above the +70°C rated specification of the
EnerChip. If such temperature excursions are not properly compensated for in the system design, the result
can be degraded performance or outright failure of the energy storage device. This Application Note provides
information on how to mitigate the detrimental effects of high temperature operation on the EnerChip in such
environments. The following topics are addressed:
• Factors that influence the operating characteristics of EnerChips and the parameters that are affected
• Effects of high temperature, bias voltage, and state of charge on operation and service life of EnerChips
• Recommendations for mitigating detrimental high temperature effects on EnerChip performance
• Configuring the EnerChip CC to offset temperature-induced effects using the integrated functions
• Operating the EnerChip in medical sterilization and high temperature food processing environments
Figure 1 illustrates the benefits of proper EnerChip management in high temperature environments.
Figure 1: Relative Capacity Retention with and
without Proper EnerChip Management
Factors affecting parameters such as cell resistance, self-discharge, and capacity fade include:
• Time
• Temperature
• State of charge (SoC)
• Bias condition (i.e., continuous charging vs. floating terminal voltage)
• Depth of discharge
With a fundamental understanding of how these factors interact to affect battery life and performance, it is
possible to deploy readily available circuit techniques to mitigate such effects. By controlling or compensating
for these factors with proper battery management, the service life of a battery that might otherwise not meet
the requirements of a given application can be greatly extended – even under operating conditions beyond the
specified rating of the battery. The data and analysis in this Application Note are presented in several forms,
describing the influence of these factors on the EnerChip and means to achieve desired performance and
service life objectives under the particular application operating conditions.
©2012 Cymbet Corporation • Tel: [phone] • www.cymbet.com
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