Electricity: battery or capacitor charging or discharging – One cell or battery charges another – Vehicle battery charging
Reexamination Certificate
1997-09-17
2001-04-24
Riley, Shawn (Department: 2838)
Electricity: battery or capacitor charging or discharging
One cell or battery charges another
Vehicle battery charging
C370S902000, C307S010100
Reexamination Certificate
active
06222341
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates generally to battery charging systems and more particularly to a system for maintaining the charge of one or more batteries in a dual-battery system.
BACKGROUND
Automobiles and other combustion engine powered vehicles typically include an electric starting motor for starting the combustion engine for operation. In this regard, the starting motor is coupled to a starting circuit which generally receives electrical energy from an on-board electric storage battery. The starting circuit selectively couples electrical energy from the battery to the starting motor that operates to cycle the engine to initiate sustained operation. In common vehicle applications, the battery also provides electrical energy to a variety of electric power consuming devices such as engine control electronics, lighting systems, and vehicle accessories.
Traditional batteries for these applications, often referred to as starting, lighting and ignition (SLI) batteries, are multi-cell, lead-acid batteries. That is, the batteries are constructed from lead plates pasted with active material and arranged into stacks. The stacks are inserted into partitioned cell compartments of a battery container, electrically connected, and flooded with dilute acid electrolyte. SLI batteries of this construction are more than adequate for providing the relatively high power demand required of engine starting as well as the relatively low power demand to maintain electrical accessories during both vehicle operation and periods of non-operation. However, because of the seemingly disparate functions the SLI battery is required to perform, short duration high-power output and long duration low-power output, the battery design can not be optimized for performing either of these tasks. An additional drawback of these batteries is relatively low specific energy (kilo-watt hours/grams (kWh/g)) as compared to other battery constructions owing to the weight of the lead plates and the liquid electrolyte.
There has been suggested a battery system for vehicle use which includes two batteries. A first battery in the system, a starting battery, is optimized for engine starting, that is, designed specifically for short duration, high-power output. A second battery in the system, a reserve battery, is optimized for operating and maintaining non-starting electrical loads. An advantage of such a system is that the starting battery may be made smaller and lighter yet capable of provide a high power output for a short period of time. In addition, the reserve battery may be made smaller and lighter yet capable of satisfying the relatively low power requirements of the vehicle accessories. In combination, the two battery system may require less space and weigh less than a single traditional SLI battery.
A limitation of such a system lies with the starting battery. Small, light weight batteries capable of high operational discharge rates typically have high self-discharge rates. That is, left unattended, the starting battery will self-discharge to a level where it is incapable of providing sufficient electrical energy for starting the engine. During vehicle operation, the starting battery is charged using the vehicle electrical system. Therefore, where the vehicle is regularly used starting battery self-discharge is not a concern. However, if the vehicle is left unused for an extended period of time or the vehicle is used for very short trips during which time the vehicle electrical system does not sufficiently charge the starting battery, the starting battery may become discharged leaving the operator stranded.
Therefore, a dual-battery system for vehicle starting and operation that provides the advantages of reduced size and weight and yet overcomes the disadvantages of starting battery self-discharge is highly desirable.
REFERENCES:
patent: 4403279 (1983-09-01), Hirsch et al.
patent: 4510431 (1985-04-01), Winkler
patent: 5002840 (1991-03-01), Klebenow et al.
patent: 5162164 (1992-11-01), Dougherty et al.
patent: 5162720 (1992-11-01), Lambert
patent: 5204610 (1993-04-01), Pierson et al.
patent: 5223351 (1993-06-01), Wruck
patent: 5281904 (1994-01-01), Tomkins
patent: 5316868 (1994-05-01), Dougherty et al.
patent: 5321627 (1994-06-01), Reher
patent: 5525891 (1996-06-01), Meyer et al.
patent: 5528087 (1996-06-01), Sibata et al.
patent: 5549984 (1996-08-01), Dougherty
patent: 5592067 (1997-01-01), Peter et al.
patent: 5637978 (1997-06-01), Kellett et al.
patent: 5668461 (1997-09-01), Hancock et al.
patent: 5668463 (1997-09-01), Duley
patent: 5717310 (1998-02-01), Sakai et al.
patent: 5760488 (1998-06-01), Sonntag
patent: 5767658 (1998-06-01), Hayes
patent: 41 38 943 C1 (1993-05-01), None
patent: 0 753 925 A2 (1997-01-01), None
patent: 2 128 044 (1984-04-01), None
patent: 2 302 622 (1997-01-01), None
patent: WO 88 08380 (1988-11-01), None
English Translation of EP 0 753 925 A2 No month.
Dougherty Thomas J.
Iverson Michael E.
Segall William P.
Johnson Controls Technology Company
Quarles & Brady LLP
Riley Shawn
Toatley Jr. Gregory J
LandOfFree
Dual battery charge maintenance system and method does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Dual battery charge maintenance system and method, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Dual battery charge maintenance system and method will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2525336