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FOR IMMEDIATE RELEASE
Yardney Built Batteries
Extend Mars Missions Beyond Expectations
Pawcatuck, CT USA - Oct 7, 2004
Lithium-Ion batteries onboard the Mars Rovers, built by Lithion, Inc,
a division of Yardney Technical Products are the lifeblood in
continuing the historic mission on Mars. The primary objectives for
the Mars Rovers were to explore the surface of the Planet for at
least 90 Martian Days. As of this publication, the Spirit Rover has
survived 181 days past it's "90 day warranty" and Opportunity has
survived 161 days passed its' similar warranty. After almost nine
months of successful operations, NASA officials have decided to fund
the project through March 2005.
Extending the effort through the Martian
winter was initially considered high risk, as the solar arrays
necessary to recharge the batteries were not sized to perform under
the harsh winter conditions. With fall and winter length of day
changes similar to those on Earth, the available sunlight necessary to
energize the solar panels decreases with each passing day. In
addition to the adverse effects of winter weather changes, dust from
the harsh winds on the surface of Mars collects on the solar panels;
further reducing their energy collection potential. Through a series
of fortunate events, to include the Lithium-Ion batteries maintaining
peak performance, the mission planners have optimized the
charging/discharging cycles to allow the vehicles to continue to roam
the planet.
In an innovative
procedure known as "leap-frogging" by the rover team, planners have
selected "lily pads" that are optimized locations on the surface to
gather the most daylight possible. This effort has increased the
sun-gathering capability of the panels, and allowed the batteries to
receive much greater re-charging energy than originally planned. With
this strategic change in roaming instructions, Lithion's power/energy
margin estimates were revised well past the 60+ days initially
projected for margin.
"We are very pleased with the
performance of our batteries. We knew the constraints on this mission
were subject to the severe weather we would encounter once we moved
out of the summer months," Vince Yevoli, Vice President and General
Manager of Lithion, stated. "With the ingenuity of the NASA mission
planners, we've been able to get a good charge on the battery. That's
all they need to get us through the winter. My bet is we'll still be
there in the Spring!"
The
two 28V, 8Ah Li-ion batteries are used to provide power to the Mars
Explorer Rover during the Martian night and to provide peak power to
the MER during the day when several scientific instruments are being
used. |
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