Batteries are not a new thing. The technology that allows electrical energy to be stored has been around for over 200 years. Allesandro Volta built such a device, in 1800, using discs of zinc and copper separated by a cloth that had been soaked in salty water. This discovery enabled an immense and growing industry. Batteries are in devices that people use almost everywhere. Most people can quickly name several cordless gadgets they use every day. These wonders of electrical power are built to accommodate hundreds of different applications in various operating conditions. They must work in temperature ranges from the sub-freezing in Antarctica to over 300 degrees Celsius in vaporizers that boil eliquids. They range in size from as large as a football field to smaller than a human hair.
Military and scientific research applications place incredible demands on energy storage technology. But the most demanding jobs performed by these power packs are probably not even on planet earth. Since the launch of Sputnik in 1957, space exploration has been using batteries in orbit and beyond. These energy applications require flawless performance in incredible conditions. There are three challenging environmental variables that rechargeable power storage systems must survive.
Shock and Vibration
Spacecraft experience dramatic levels of physical shaking and violent movement between the launch phase and arriving in orbit. One astronaut, Tom Jones, described it as feeling like, “… the entire orbiter rattled and shuddered like a skyscraper in an earthquake.” Batteries must be designed and packaged to survive a lot of shake, rattle and roll.
Variations in temperature experienced by batteries on a satellite affect their performance. Temperatures a satellite in orbit must withstand can range from as low as negative 250 degrees Celsius to as high as 300 degrees Celsius. That is colder than liquid nitrogen and three times the boiling point of water. Batteries must be designed and built to withstand these extremes.
Beyond the earth’s protective atmosphere and magnetosphere, dangerous levels of radiation exist. The kinds of damage caused by radiation include deterioration of protective coverings and excessive heat when particles of radiation collide with particles in the battery. Three chest x-rays expose a person to about one Milli-Sievert (mSv) of radiation. While orbiting Earth, power systems in a satellite could be exposed to as much as 2,000 mSv. Needless to say, batteries in space are being zapped by ionizing particles that would be devastating to many pieces of equipment.
Batteries in space are an example of the ingenuity and skill possessed by engineers and scientists. These amazing portable packages of power are a true wonder of technological progress.