EP0588613A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Battery protection circuits
Assignee: Sony Corp
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Filing: 1993-09-15
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Granted: —
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Expires: 2013-09-15
Abstract
Abstract Circuit groups for preventing a battery from deterioration in efficiency due to charging and discharging of each of plural secondary batteries are incorporated in a battery protection circuit for protecting the plurality of batteries, which are connected in series, so as thereby to extend the life of the battery. The battery protection circuit incorporates power down means for extending as much as possible a time in which a voltage of a remaining capacity becomes OV by causing a current to flow only in minimum circuitry when the battery is overdischarged. Also, when a trouble such as a momentary overcurrent or the like is detected, the circuit can be prevented from being set in a power down mode.
Inventors
- 👤 Yasuhito C/O Intellectual Property Div. Eguchi
- 👤 Kanji C/O Intellectual Property Div. Murano
- 👤 Akira C/O Sony Energytec Inc. Sanpei
- 👤 Hajime Tamiya
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-10 02:36
CPC Classifications
H; H02; H02J; H02J7/00; H02J7/50; H02J7/52; H02H; H02H7/00; H02H7/18; H02J7/60; H02J7/663
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
196 words
A battery protection circuit for a secondary battery, the circuit comprising: state detecting means for detecting a voltage of a secondary battery and detecting an overdischarged or overcharged state of said secondary battery by comparing said detected voltage with a reference voltage; first switching means for interrupting a discharging current; second switching means for interrupting a charging current; control means for controlling the switching of said first and second switching means on the basis of a detected result of said state detecting means; power down switching means for interrupting a voltage and a reference voltage supplied to said state detecting means; power down means for making said power down switching means nonconductive when the overcharged state of said secondary battery is detected by said state detecting means; power down releasing means for returning said power down switching means from the nonconductive state to a conductive state when charging of said secondary battery is started again from the overdischarged state; and state holding means for detecting that said secondary battery has started to be charged again from the overdischarged state by a charging voltage produced across terminals of said secondary battery and holding the detected charging state.
Claim 2
Dependent Claim
30 words
A battery protection circuit according to claim 1, wherein said state holding means holds said charging state until a voltage of said secondary battery gets away from an overdischarging region.
Claim 3
Dependent Claim
46 words
A battery protection circuit according to claim 1 for a plurality of secondary batteries connected in series, wherein said power down means makes said power down switching means nonconductive when an overdischarged state of at least one secondary battery is detected by said state detecting means.
Claim 4
Dependent Claim
47 words
A battery protection circuit according to claim 3, wherein said power down releasing means makes a reference voltage power down switching means in said state detecting means conductive at first and makes other power down switching means conductive after the occurrence of a reference voltage is detected.
Claim 5
Dependent Claim
47 words
A battery protection circuit according to claim 4, comprising means for forcing said secondary battery to be set in a state in which said secondary battery can be charged when said power down switching means is nonconductive and a voltage of said secondary battery is substantially OV.
Claim 6
Dependent Claim
35 words
A battery protection circuit according to claim 3, comprising power down inhibiting means for holding said power down switching means in the conductive state when any of said secondary batteries is in the overcharged state.
Claim 7
Dependent Claim
45 words
A battery protection circuit according to claim 6, comprising overcurrent detecting means for detecting a large current flowing momentarily, and in which said power down inhibiting means is inhibited from being made nonconductive on the basis of a detection signal from said overcurrent detecting means.
References Cited (Backward Citations)
No citation records indexed.
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