Lithium polymer battery powered intravenous fluid warmer

• US 7,956,583 B2
• Filed: 06/21/2010
• Issued: 06/07/2011
• Est. Priority Date: 11/07/2005
• Status: Expired due to Fees

• Current Assignee: Vital Signs Incorporated (Becton, Dickinson & Co)
• Original Assignee: General Electric Company
• Inventors: Cassidy, David
• Primary Examiner(s): Tso; Edward
• Assistant Examiner(s): HERNANDEZ, MANUEL J
• Application Number:
  US12/820,094
• Publication Number:
  US 20100253288A1
• Time in Patent Office: 351 Days
• Field of Search: 320/150, 320/152, 320/154
• US Class Current: 320/152
• CPC Class Codes: A61M 2205/8206 battery-operated
• CPC Class Codes: A61M 5/44 having means for cooling or heating the devices or media
• CPC Class Codes: B60L 2240/545 Temperature
• CPC Class Codes: B60L 2250/16 by display
• CPC Class Codes: B60L 3/0046 relating to electric energy storage systems, e.g. batteries or capacitors
• CPC Class Codes: B60L 58/14 Preventing excessive discharging
• CPC Class Codes: B60L 58/15 Preventing overcharging
• CPC Class Codes: B60L 58/22 Balancing the charge of battery modules
• CPC Class Codes: B60L 58/24 for controlling the temperature of batteries
• CPC Class Codes: B60L 58/25 by controlling the electric load
• CPC Class Codes: B60L 58/27 by heating
• CPC Class Codes: H01M 10/052 Li-accumulators
• CPC Class Codes: H01M 10/0565 Polymeric materials, e.g. gel-type or solid-type
• CPC Class Codes: H01M 10/425 Structural combination with electronic components, e.g. electronic circuits integrated to the outside of the casing printed circuits H05K1/00
• CPC Class Codes: H01M 10/46 Accumulators structurally combined with charging apparatus circuits for charging H02J7/00
• CPC Class Codes: H01M 10/482 for several batteries or cells simultaneously or sequentially
• CPC Class Codes: H01M 10/486 for measuring temperature
• CPC Class Codes: H01M 10/488 Cells or batteries combined with indicating means for external visualization of the condition, e.g. by change of colour or of light density
• CPC Class Codes: H01M 2010/4271 Battery management systems including electronic circuits, e.g. control of current or voltage to keep battery in healthy state, cell balancing
• CPC Class Codes: H01M 2010/4278 Systems for data transfer from batteries, e.g. transfer of battery parameters to a controller, data transferred between battery controller and main controller
• CPC Class Codes: H01M 2200/103 : Fuse
• CPC Class Codes: H01M 2220/30 : Batteries in portable systems, e.g. mobile phone, laptop
• CPC Class Codes: H02J 2310/23 : The load being a medical device, a medical implant, or a life supporting device
• CPC Class Codes: H02J 7/0013 : acting upon several batteries simultaneously or sequentially H02J7/1423 takes precedence
• CPC Class Codes: H02J 7/00309 : Overheat or overtemperature protection
• CPC Class Codes: H02J 7/0031 : using battery or load disconnect circuits H02J9/002 takes precedence
• CPC Class Codes: Y02E 60/10 : Energy storage using batteries
• CPC Class Codes: Y02T 10/70 : Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 90/16 : Information or communication technologies improving the operation of electric vehicles

Abstract

A lithium polymer (LiPo) battery pack having LiPo battery cells is provided which includes battery protection circuitry, charging circuitry, cell balancing circuitry, and control and communication circuitry. The batteries can be charged while in use by an internal charger. Battery charging and discharging are accomplished in a controlled and protected manner to avoid overcharging and overdischarging conditions. The novel battery pack has built-in safeguards against dangerous LiPo battery conditions and is implemented in a small, portable unit which contains the battery cells, control and protection circuitry, internal charger and display gauge. The battery pack is useful for powering an intravenous fluid warmer or other medical or electrical devices and equipment.

Claims

1. Apparatus for warming a fluid, the apparatus comprising:

a first conductive path from an external power source to a heater;

a second conductive path from a battery to the heater;

a third conductive path from the first conductive path to a charger, wherein the charger is coupled to the battery through a fourth conductive path, where at least one portion of the second conductive path is not common with the first, third and fourth conductive paths and the at least one portion is only used for discharge current to the heater;

a first order battery protection circuit, coupled to at least one sensor and a battery disconnect switch located between the third and fourth conductive paths, for disconnecting the battery from the charger in response to a first predetermined condition;

a second order battery protection circuit, coupled to the at least one sensor and a thermal fuse located between the first and second conductive paths, for opening the thermal fuse in response to a second predetermined condition; and

a fluid warmer over temperature protection circuit, coupled to the thermal fuse, for opening the thermal fuse in response to excessive fluid temperature.

2. The apparatus of claim 1, wherein the at least one sensor is a stress sensor.

3. The apparatus of claim 1, wherein the battery comprises a plurality of cells, and wherein the first predetermined conditions is a dimension of at least one of the plurality of cells.

4. The apparatus of claim 1, wherein the battery comprises a plurality of cells, and wherein the first predetermined conditions is a pressure inside at least one of the plurality of cells.

5. The apparatus of claim 1, wherein the battery comprises at least one lithium polymer cell.

6. A battery pack for a fluid warmer, comprising:

a plurality of lithium polymer cells;

a charger connected to the plurality of lithium polymer cells;

a spread spectrum oscillator, connected to the charger, for providing a waveform having low electromagnetic interface characteristics;

a first order battery protection circuit, coupled to at least one sensor and a battery disconnect switch, for disconnecting the battery from the charger in response to a first predetermined condition;

a second order battery protection circuit, coupled to the at least one sensor and a thermal fuse, for opening the thermal fuse in response to a second predetermined condition; and

a fluid warmer over temperature protection circuit, coupled to the thermal fuse, for opening the thermal fuse in response to excessive fluid temperature.

7. The battery pack of claim 6, wherein the at least one sensor is a plurality of temperature sensors.

8. The battery pack of claim 7, wherein a plurality of temperature sensors are attached to the plurality of lithium polymer cells in a distributed manner.

9. The battery pack of claim 6, wherein the at least one sensor is a voltage sensor.

10. The battery pack of claim 6, wherein the at least one sensor is a current sensor.

11. The battery pack of claim 6, wherein the at least one sensor is a stress sensor.

12. The battery pack of claim 6, wherein the at least one sensor is a strain sensor.

13. The battery pack of claim 6, further including a battery condition indicator coupled to the first order battery protection circuit and having a display.

14. The battery pack of claim 6, further including a battery condition indicator coupled to the first order battery protection circuit and having an annunciator.

15. The battery pack of claim 6, wherein the charger is coupled to the plurality of lithium polymer cells such that the charger directs a discharge load current on a path partially separate from a path of charging current.

16. The battery pack of claim 6, wherein an electric current output from the battery pack conducts in a circuit partially separate from the charger.

17. The battery pack of claim 6, further including a fire and/or explosion resistant enclosure containing at least the plurality of lithium polymer cells.