# US 2008/0185994 A1 · Low-power battery system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2008/0185994 A1 - Document ID: US20080185994A1 - Status: Published application - Kind: A1 - Application number: 12/028,600 - Filed: 2008-02-08 - Published: 2008-08-07 - Earliest claimed: 2006-05-31 - Assignees: Aeroflex Plainview, Inc. - Inventors: George Altemose - Web page: https://patentgrep.com/patent/US20080185994A1 ## CPC - H02J 7/54: Passive balancing, e.g. using resistors or parallel MOSFETs - H01M 10/425: {Structural combination with electronic components, e.g. electronic circuits integrated to the outside of the casing (printed circuits H05K1/00)} - H01M 10/441: {for several batteries or cells simultaneously or sequentially} - H01M 2010/4271: {Battery management systems including electronic circuits, e.g. control of current or voltage to keep battery in healthy state, cell balancing} - Y02E 60/10: Energy storage using batteries - H02J: ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY - H01M: PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION ## Abstract A system for balancing the charge level of a plurality of electrically coupled battery units. The system configuration may utilize an architecture and/or methodology that is more appropriate for lower power applications. In particular, the present invention, in accordance with at least one embodiment, may provide a battery balancing system that implements low loss charge balancing circuits in a compact configuration suitable for a multitude of applications, such as smaller cell battery balancing. The charge balancing circuits may be incorporated within each battery unit. ## Claims ### Claim 1 A battery system, comprising: a plurality of battery units electrically coupled to at least a common bus, each of the plurality of battery units including one or more battery cells and a battery balancing circuit, wherein each battery balancing circuit is configured to balance the charge of the one or battery cells in the plurality of battery units utilizing the common bus; and a system clock coupled to the plurality of battery units. ### Claim 2 (depends on 1) The battery system of claim 1, wherein the each of the plurality of battery units further comprises a housing, the housing being configured to contain the one or more battery cells and the battery balancing circuit. ### Claim 3 (depends on 1) The battery system of claim 1, wherein each of the one or more battery cells comprises a plurality of battery cells electrically coupled in parallel to form a virtual battery cell. ### Claim 4 (depends on 1) The battery system of claim 1, wherein the plurality of battery units are also electrically coupled to each other in series to form a battery. ### Claim 5 (depends on 1) The battery system of claim 1, wherein all of the one or more battery cells in the plurality of battery units are electrically coupled in series; and all of the battery balancing circuits in the plurality of battery units are electrically coupled to at least the one or more battery cells and the system clock. ### Claim 6 (depends on 1) The battery system of claim 1, wherein each battery balancing circuit is configured to allow current to flow over the common bus from one or more battery cells with a higher charge to one or more battery cells with a lower charge until all of the one or more battery cells have the same charge. ### Claim 7 (depends on 1) The battery system of claim 1, wherein the battery balancing circuit comprises capacitors and inverters in order to reduce any losses caused by the battery balancing circuit. ### Claim 8 (depends on 1) The battery system of claim 1, wherein the battery balancing circuit comprises transistors, resistors, capacitors and diodes in order to reduce any losses caused by the battery balancing circuit. ### Claim 9 (depends on 1) The battery system of claim 1, wherein the battery balancing circuits are configured to allow current to flow over the common bus from one or more battery cells with a higher charge to one or more battery cells with a lower charge in accordance with at least one clock signal produced by the system clock. ### Claim 10 (depends on 9) The battery system of claim 9, wherein the system clock is configured to produce two clock signals including a phase gap between the two clock signals. ### Claim 11 A battery balancing method, comprising: electrically coupling a plurality of battery units to at least a common bus and a system clock, each of the plurality of battery units including one or more battery cells and a battery balancing circuit; and configuring the battery balancing circuit in each of the plurality of battery units to balance the charge of the one or battery cells in the plurality of battery units utilizing the common bus. ### Claim 12 (depends on 11) The method of claim 11, wherein the each of the plurality of battery units further comprises a housing, the housing being configured to contain the one or more battery cells and the battery balancing circuit. ### Claim 13 (depends on 11) The method of claim 11, wherein each of the one or more battery cells comprises a plurality of battery cells electrically coupled in parallel to form a virtual battery cell. ### Claim 14 (depends on 11) The method of claim 11, wherein the plurality of battery units are also electrically coupled to each other in series to form a battery. ### Claim 15 (depends on 11) The method of claim 11, wherein all of the one or more battery cells in the plurality of battery units are electrically coupled in series; and all of the battery balancing circuits in the plurality of battery units are electrically coupled to at least the one or more battery cells and the system clock. ### Claim 16 (depends on 11) The method of claim 11, further comprising configuring each battery balancing circuit to allow current to flow over the common bus from one or more battery cells with a higher charge to one or more battery cells with a lower charge until all of the one or more battery cells have the same charge. ### Claim 17 (depends on 11) The method of claim 11, wherein the battery balancing circuit comprises capacitors and inverters in order to reduce any losses caused by the battery balancing circuit. ### Claim 18 (depends on 11) The method of claim 11, wherein the battery balancing circuit comprises transistors, resistors, capacitors and diodes in order to reduce any losses caused by the battery balancing circuit. ### Claim 19 (depends on 11) The method of claim 11, further comprising configuring the battery balancing circuits to allow current to flow over the common bus from one or more battery cells with a higher charge to one or more battery cells with a lower charge in accordance with at least one clock signal produced by the system clock. ### Claim 20 (depends on 11) The method of claim 11, wherein the system clock is configured to produce two clock signals including a phase gap between the two clock signals.