Method and device for charging lead accumulators

• US 5,701,069 A
• Filed: 01/03/1996
• Issued: 12/23/1997
• Est. Priority Date: 05/24/1993
• Status: Expired due to Term

• Current Assignee: Bengt Arrestad Fastighets Aktiebolag
• Original Assignee: Livingstones Patenter AB
• Inventors: Wihk, Bernt E L
• Primary Examiner(s): Wong, Peter S.
• Assistant Examiner(s): TOATLEY, GREGORY J
• Application Number:
  US08/553,484
• Time in Patent Office: 720 Days
• Field of Search: 320/14, 320/21, 320/27, 313/24 R, 313/239
• US Class Current: 320/130
• CPC Class Codes: H02J 2207/20 Charging or discharging characterised by the power electronics converter
• CPC Class Codes: H02J 7/00711 with introduction of pulses during the charging process
• CPC Class Codes: H02J 7/02 for charging batteries from ac mains by converters

Abstract

According to the invention, lead storage batteries are charged by intermittently switching on and off a battery-charging unit (1, 2, 3) which is connected to a battery. The on and off times are suitably about 1 second when charging a battery. In the case of a maintenance charge, it is suitable to charge the battery with pulses in the region of a mains voltage period, with pauses of about 10 seconds. The circuit is suitably broken by means of a switch (4, 5) on the primary side of the transformer (1, 2). The switch may have the form of a relay with associated time circuit (4), although it is preferred to use a triac.

Claims

1. A method for charging lead storage batteries, comprising applying a varying direct voltage from a battery-charging unit which is sufficient to generate gassing at the positive and negative pole, characterized in that this gassing is achieved by applying the direct voltage in intermittent current supply periods that are interrupted with pauses in which no current is supplied, having durations of between about 0.5 seconds and about 10 seconds wherein the current supplied to the battery is non-negative throughout the method.

2. A method according to claim 1, characterized in that the current supply periods and the pauses have generally the same durations.

3. A method according to claim 1 for regenerating batteries whose cells are in mutually different states, characterized by charging, discharging and charging the battery several times until all of its cells have been regenerated.

11. A method as claimed in claim 1, wherein during the pauses the current is substantially zero.

4. A device for charging lead storage batteries comprising a transformer having a primary winding for connection to the electrical main, a secondary winding, a rectifier connected to the secondary winding, and a positive and a negative terminal intended for connection to a battery to be charged, characterized by an automatic switch means connected to the primary winding for selectively coupling the main on and off intermittently to the primary winding with short battery-charging periods interrupted by pauses in which no current is supplied, having durations of from 0.5 to 10 seconds, wherein said battery charging periods and said pauses between these charging periods are sufficient to generate gassing at the positive and negative pole in said batteries and the supplied current is non-negative.

5. A device according to claim 4, characterized in that the switch means is adapted to switch the mains network on and off over time periods of essentially equal durations.

6. A device according to claim 4, characterized in that the switch means includes a two-way extinguishable semi-conductor valve which functions as a single-pole switch.

7. A device according to any one of claims 4-6, characterized in that the transformer has three primary windings intended for connection to a three-phase network;

and in that the switch means is connected between the three-phase network and the transformer in one of the phase conductors.

8. A method for charging lead storage batteries, comprising applying a varying direct voltage from a battery-charging unit which is sufficient to generate gassing at the positive and negative pole, characterized in that this gassing is achieved by applying the direct voltage in intermittent current supply periods that are interrupted with pauses in which no current is supplied, the current supply periods and the pauses having durations of from 0.5 to 1.5 seconds, wherein the supplied current is non-negative.

9. A method for maintaining the charge of fully charged lead storage batteries, comprising applying a varying direct voltage from a battery-charging unit which is sufficient to generate gassing at the positive and negative pole, characterized in that this gassing is achieved by applying the direct voltage in intermittent current supply periods that are interrupted with pauses in which no current is supplied, the intermittent current supply pulses having a duration of not more than one-half second, and the pauses having durations of from 0.5 to 10 seconds, wherein the supplied current is non-negative.

10. A device for charging lead storage batteries comprising a transformer having a primary winding for connection to the electrical main, a secondary winding, a rectifier connected to the secondary winding, and a positive and a negative terminal intended for connection to a battery to be charged, characterized by an automatic switch means connected to the primary winding for selectively coupling the electrical main on and off intermittently to the primary winding with short battery-charging periods interrupted by pauses in which no current is supplied, the switch means being set between a battery charging state in which the activation time periods are from 0.5 to 10 seconds duration, and a battery charge-maintaining state in which the charge-maintaining periods have a maximum duration of 0.5 seconds, wherein said battery charging periods and said pauses between these charging periods are sufficient to generate gassing at the positive and negative pole in said batteries and the supplied current is non-negative.