Handheld medical equipment power supply

When the range of medical equipment from hospital to emergency and family medical environment, its mobility will is determined by a number of factors.

In addition, the hospital's medical equipment often need battery support for patients in different hospital wards in the transfer.

Also, reproductive boomers people has entered the elderly, they still hope that scattered activities, this is the traditional fixed equipment for portable applications has created a demand for these devices to facilitate the activities of the sick elderly.

They include a diagnostic instrument, such as, in addition to fiber fibrillation ultrasonic equipment and blood Analyzer; there is also a device for patients, including insulin syringes, left ventricular assist device (LVADs) and wireless signal monitor life.

In addition, when multiple surgical instruments can only be used within a certain scope, some of the instruments are related to the use of battery-powered and get rid of this limitation.

Like electric plastic tools or endoscopic surgical equipment such as using battery power, the surgeon felt that flexibility brings great convenience.

Traditional battery pack contains the main energy supplied and integrated the remaining battery power, protection circuit, temperature sensor, display the battery or battery status led driver and serial data communication bus circuit boards.

External battery pack is a typical plastic shell that comes with the with the master can be connected with electrical interface external touch points and absorb vibration and maintaining internal and external components of the insulation.

Use profiles

Design a safe and reliable system for the first step is to accurately understand medical device use model called features, these features include the temperature range, discharge curves, charging, save life and transmission needs.

Application for mobile device selection of optimal battery, all external and internal operating temperature also are important considerations.

Manufacturers indicate the batteries in the ideal of constant current C/5 and + 20 ° c external temperature performance.

However, many medical devices are expected to be able to work at-20 ° c ~ + 60 ° c temperature range, and heat can charge and discharge process, lion and when battery system with temperature-sensitive components together, the combination of battery systems and equipment housings have maximum temperature threshold.

An inconsistent pulse discharge or typical defibrillators of pulse will cause the batteries to produce more heat, compared to non-uniform discharge curve, this situation can be faster to reduce battery capacity.

While charging the battery heat dissipation effects, should be taken into account in the design of battery systems.

Optimization property

To select the best batteries battery pack determines the field medical equipment works correctly, it needs to have full battery performance curve.

Learn about the voltage, charge and discharge cycles, load current, the energy density, charging time and discharge rate, and other indicators for handheld device select the cell in the first step, below to the standard to describe several batteries.

First of all be sealed lead acid batteries (SLA).

Rechargeable SLA's features include: rated voltage of 2V, Prism or cylindrical structure, large capacity, low cost and simple charging conditions. SLA batteries biggest challenges include: large bulky volume factors, linear voltage attenuation, lack of fast charge technology and on the high temperature and high self discharge sensitivity (this affects save life).

Followed by the NiMH battery.

Its features include: 1.25V rated voltage, the life of 500 charge and discharge cycles, 100Wh/kg average energy density, charging time is less than four hours, almost 30 per cent of the monthly discharge rate and strict size factor. In a demand for low-voltage or price sensitive places, NiMH batteries have a very good performance, 10 NiMH batteries can concatenate to increase voltage so that the total voltage reaches 12.5V.

Finally the lithium-ion battery.

Characteristics of lithium ion batteries included: 3.6V rated voltage and in the life of 500 to 1000 of charging and discharging cycles, the average energy density is 160Wh/kg, charging time is less than 4 hours per month average discharge rate of 10 per cent; 7 lithium-ion battery can be threaded together so that the total voltage reaches 25.2V.

Intelligent battery pack

Handheld and outdoor is the current trend of medical equipment.

Lithium-ion battery with higher energy density, lighter weight, more long work cycle, superior capacity retention and wide ambient temperature adaptability, relative to the same power of NiMH and SLA solution, it requires less number of batteries.

The Board of many advanced attachments promote a system of intelligent, these attachments including residual power, protection circuit, temperature sensor and serial data bus.

A smart battery pack, when the end user's discharge curve or characteristics adapted, can provide higher power utilization. Battery pack for the medical applications of worthwhile because it has the ability to monitor their own State, can accurately predict the remaining running time and work groups States sent to medical devices. These features allow the end user can use intelligent management device, but also to avoid unexpected failures or shutdowns. An intelligent battery pack can be used according to its history, such as making feedback traceability and guarantees provide convenience.

Security

Medical batteries must integrate multiple security systems and reliable protection circuit.

Where the activities of the safety circuit is to ensure that the battery of chemical substances remain stable State must factor. Safety circuit protection battery from overcharge and discharge, short circuit and extreme temperatures, the voltage shall be limited to the strict scope of work. Safety circuit through the battery temperature sensor at a particular temperature circuit breaker to prevent heat dissipation and overheating.

For multiple-cell battery pack, have an active cell balancing circuit is wise.

The circuit is placed in the battery pack in a particular key, as this makes the battery is no longer a risk of overheating.