Page 19 - PEN Ebook May 2021
P. 19
TEST & MEASUREMENTS Test & Measurements
over the sensing area. The sensor transforms
When considering materials and construction of a
battery, evaluating the pressure dynamics is critical compressive pressure loads to a change in
to maintain the material spacings, control gassing, resistance.
and prevent excess swelling. → Sensors typically have about 2,000 sensing
points, but some sensors can be designed
with over 16,000 sensing points.
WHAT IS PRESSURE MAPPING? → Sensing element spacing (pitch) can be as
Even between relatively flat surfaces, you might narrow as 0.64 mm (0.025 in.).
find the interface pressure distribution is often not → Sensors can measure pressure ranges up
uniform within localized areas of peak pressure. to 25,000 PSI (172 MPa)
Pressure mapping technology helps design engi- → High-temperature sensor options up to
neers obtain insight into areas that may impact 200°C (400°F)
design and quality.
▶ The scanning electronics collect analog data
As shown in Figure 1, pressure mapping systems from the sensor and convert the data into a
are made of three components – sensors, scanning digital signal.
electronics, and software – to deliver real-time, → Scanning speeds available up to 20,000 Hz
actionable data, in ways other methods cannot.
▶ The software displays real-time activity of
A Novel Method for ▶ The sensor is an array of piezoresistive sens- the sensor area, allowing users to see force,
pressure, contact area, and timing data.
ing points that measure pressure distribution
Measuring Pressure
Exchanges within
Battery Housing for
Lifecycle Testing
By Camilo Aladro, Pressure Mapping Product Manager, Tekscan, Inc.
Many of those that are familiar with the construc- Regardless of the industry, consumer electronics,
tion of a prismatic lithium-ion battery will say that or energy storage systems to name a few, users are
it breathes. Charging and discharging causes tem- requesting batteries that are lighter, more compact,
perature changes, electrochemistry, and mechanics have a higher energy density and faster charging.
of the internal components that, in turn, change They must also be safe in the event of catastrophic
the internal pressures. As manufacturers try to incidents. These features can often be in conflict, it
create a product that is efficient, lightweight, and can be a challenge to find a balance and stay cost
safe, it is of paramount importance that designers competitive.
Figure 1: Designers and engineers use pressure mapping systems, such as the one shown above, to measure interface pressure
intimately understand these characteristics. between two mating surfaces.
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