Hospital Applications
There are many types of equipment, used in the hospital or long term care facility, that require battery power. Traditionally battery power was required for these applications for back-up and thus were based on sealed lead acid batteries. Sealed lead acid batteries are simple to employ and inexpensive, but they are big and heavy with poor cycle life. Long runtime, light weight, good cycle life and accurate fuel gauging is required for the new generation of hospital equipment, so Li-ion is the chemistry of choice. Micro Power has experience in the design and manufacture of batteries and chargers for medical equipment used in a hospital environment. Some examples include of products that are migrating to Li-ion chemistry include:
- Medical workstations
- Patient monitors
- Motorized gurneys
- Electric wheelchairs
- Ventilators
- Defibrillators
- Infusion pumps
- EEG monitors
- ECG monitors
- Pulse oximeters
- Nebulizers
- Portable ultrasound
Un-Interrupted Power for the Hospital Environment:
Medical devices that provide 24-hr support for patients are going mobile. New scientific evidence supports the idea that mobility results in the best long term outcome for a patient. In addition, quality of life and costs are improved with mobility and flexibility. Life-support devices, therapy devices, and diagnostic equipment all have a requirement for uninterrupted 24hr battery power. Examples of these applications include ventricular assist devices, ventilators and oxygen concentrators. The innovative new power systems for uninterrupted power consist of two high capacity batteries that are charged with a "smart" micro-controlled power management system. The batteries for these applications feature the latest in gas gauging, and readouts for remaining runtime, charge time and low power. The two battery design allows the batteries to be "hot swapped" for uninterrupted use and unlimited runtime.
Sealed Lead Acid Replacement:
Li-ion advantages over sealed lead acid include a much higher energy density, lighter weight, longer cycle-life, superior capacity retention and broader ambient-temperature endurance. For their size and weight Li-ion cells store and deliver more energy than other rechargeable batteries. In addition, Li-ion delivers a lower total cost of ownership for the end customer because of its long cycle life and low environmental impact. Micro Power's Lithium Iron Phosphate batteries are a great match for sealed lead acid replacement; they accept the existing charger directly and provide approximately the same voltage with better runtime and cycle life.
Fuel Gauging:
Traditional fuel gauges for Li-ion either monitored the voltage or the capacity, and the accuracy was quite limited. This is due to that flat discharge curve we saw earlier. New gas gauges monitor the number of coulombs being transferred and opportunistically calibrates with the open circuit voltage of the Li-ion pack. These features allow the end-user to intelligently manage device use and avoid unexpected failures or shutdowns. Accurate fuel gauging, combined with smart charging algorithms enable Li-ion packs to meet the needs of even life support applications.
