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EP-4736292-A1 - A DRIVER ARRANGED TO BE CONNECTED TO A BATTERY MANAGEMENT SYSTEM, BMS, AS WELL AS A CORRESPONDING METHOD

EP4736292A1EP 4736292 A1EP4736292 A1EP 4736292A1EP-4736292-A1

Abstract

A driver arranged to be connected to a Battery Management System, BMS, said BMS comprising a battery, wherein the driver comprises a voltage control unit arranged to control a voltage provided to said BMS for charging said battery, wherein said voltage provided to said BMS gradually increases to a charging voltage and a current control unit arranged to control a current provided to said BMS wherein said current provided to said battery is set at a safety current value during a time that said voltage gradually increases and is then increased to a nominal current value once said charging voltage has been reached.

Inventors

  • EBERSON, ETIENNE, NICOLAAS, KATHALIJNTJE, PAULUS, MARIE
  • KROEZE, Zadok, Vitalis, Socrates

Assignees

  • Signify Holding B.V.

Dates

Publication Date
20260506
Application Date
20240626

Claims (13)

  1. 1. A driver (302) arranged to be connected to a Battery Management System, BMS (304), said BMS (304) comprising a battery, wherein the driver (302) comprises: a voltage control unit arranged to control a voltage (3e, 53e) provided to said BMS (304) for charging said battery, wherein said voltage (3e, 53e) provided to said BMS (304) gradually increases to a charging voltage; a current control unit arranged to control a current (3f, 531) provided to said BMS (304) wherein said current (3f, 531) provided to said battery is set at a safety current value during a time that said voltage gradually increases and is then increased to a nominal current value once said charging voltage has been reached, a processing unit arranged for: keeping track of a number of times said battery is disconnected within a predefined time window and for stopping said providing said voltage and said current to said BMS (304) when said number of times exceed a predefined reset counter; and/or keeping track of a time required for said battery to charge to a battery voltage and for stopping said providing said voltage and said current to said BMS (304) when said tracked time exceeds of predefined time period.
  2. 2. A driver (302) in accordance with claim 1, wherein said voltage control unit is arranged to gradually increase said charging voltage by stepwise increments.
  3. 3. A driver (302) in accordance with any of the previous claims, wherein said current control unit is arranged to gradually increase said current from said safety current value to said nominal current value once said charging voltage has been reached.
  4. 4. A driver (302) in accordance with claim 3, wherein said current control unit is arranged to gradually increase said current from said safety current value to said nominal current value once said charging voltage has been reached, by stepwise increments.
  5. 5. A driver (302) in accordance with any of the previous claims, wherein said voltage control unit is arranged for determining that a voltage over said battery is above a predefined safety threshold, and for triggering said current control unit to start with gradually increasing said current provided to said battery.
  6. 6. A method for managing a driver (302) in accordance with any of the previous claims, wherein said driver (302) is arranged for driving a Battery Management System, BMS (304), wherein said BMS (304) comprises a battery, wherein said method comprises the steps of: controlling, by said voltage control unit, a voltage provided to said BMS (304) for charging said battery, wherein said voltage provided to said BMS (304) gradually increases to a charging voltage; controlling, by a current control unit, a current provided to said BMS (304), wherein said current provided to said BMS (304) is set at a safety current value during a time that said voltage gradually increases and is then increased to a nominal current value once said charging voltage has been reached.
  7. 7. A method in accordance with claim 6, wherein said step of controlling said voltage comprises: gradually increasing said charging voltage by stepwise increments.
  8. 8. A method in accordance with any of the claims 6 - 7, wherein said step of controlling said current comprises: gradually increasing said current from said safety current value to said nominal current value once said charging voltage has been reached.
  9. 9. A method in accordance with claim 8, wherein said step of gradually increasing comprises: gradually increasing said current from said safety current value to said nominal current value once said charging voltage has been reached, by stepwise increments.
  10. 10. A method in accordance with any of the claims 6 - 9, wherein said driver (302) further comprises a processing unit, and wherein said method comprises the step of: keeping track, by said processing unit, of a number of times said battery is disconnected within a predefined time window and for stopping said providing said voltage and said current to said BMS (304) when said number of times exceed a predefined reset counter.
  11. 11. A method in accordance with any of the claims 6 - 10, wherein said driver (302) comprises a processing unit, and wherein said method comprises the step of: keeping track, by said processing unit, of a time required for said battery to charge to a battery voltage and for stopping said providing said voltage and said current to said BMS (304) when said tracked time exceeds of predefined time period.
  12. 12. A method in accordance with any of the claims 6 - 11, wherein said method comprises the step of: determining, by said voltage control unit, that a voltage over said battery is above a predefined safety threshold, and for triggering said current control unit to start with gradually increasing said current provided to said battery.
  13. 13. A computer program product comprising a computer readable medium having instructions stored thereon which, when executed by a driver (302), cause said driver (302) to implement a method in accordance with any of the claims 6 - 12.

Description

A DRIVER ARRANGED TO BE CONNECTED TO A BATTERY MANAGEMENT SYSTEM, BMS, AS WELL AS A CORRESPONDING METHOD FIELD OF THE INVENTION The present disclosure generally relates to the field of Emergency lighting systems comprising a Battery Management System, BMS, and, more specifically, to a driver to be connected to such a BMS. BACKGROUND OF THE INVENTION Emergency lighting systems incorporate a battery, typically utilizing various technologies, including lithium-ion, Li-ion, batteries. These Li-ion battery packs are equipped with a Battery Management System, BMS, responsible for safeguarding against unsafe situations and optimizing battery lifespan. The BMS may act as a switch, thereby disconnecting the battery pack in the event of hazardous occurrences such as a short-circuit within a cell or load, excessively deep discharge, or overcharge. When a completely safe too-deep-discharge condition arises, the BMS promptly disconnects the battery pack from the charger in the emergency driver, ensuring protection. However, an inherently dangerous condition, such as a bulging or short-circuited cell, triggers the same response - disconnection of the battery pack by the BMS. The charger in the emergency driver cannot differentiate between these safe and potentially unsafe conditions. Consequently, some emergency drivers available in the market adopt a simplistic approach by automatically resetting the BMS whenever the mains voltage is switched on. This reset is accomplished by applying a higher voltage to the battery than the voltage release threshold, while limiting the current to its maximum value. This procedure is acceptable when the BMS disconnects the battery pack due to a safe condition, such as a too-deep-discharge. However, when the battery pack is disconnected due to an unsafe condition like a short-circuited or bulging cell, this resetting mechanism poses a concern. Each time the charger is restarted, the hot-spot within the battery pack becomes energized. Consequently, with every activation of the hot spot, the condition worsens, potentially escalating the risk. Given the relatively small size of the hot spot and the presence of multiple cells within a battery pack, detecting this failure mode with absolute certainty using a simple Negative Temperature Coefficient, NTC, sensor located on a single cell is not feasible. Therefore, it may be of importance to consider more advanced detection and protection mechanisms for emergency lighting systems. These could involve incorporating sophisticated sensors capable of identifying hazardous conditions accurately. By implementing an advanced monitoring system that can assess the overall health of the battery pack, including the status of individual cells, it would be possible to mitigate risks effectively. While battery packs in emergency lighting systems are equipped with a BMS to ensure safety, distinguishing between safe and potentially unsafe conditions solely based on charger behaviour is challenging. Relying on simplistic resetting methods may exacerbate the risks associated with unsafe conditions. Hence, exploring advanced detection and protection strategies, such as comprehensive monitoring systems, becomes imperative to enhance the safety and reliability of emergency lighting systems using Li-ion batteries. SUMMARY OF THE INVENTION It would be advantageous to obtain a driver that is to be connected to a Battery Management System, BMS, wherein the driver is adapted to prevent unsafe situations at the BMS side. It would further be advantageous to obtain a corresponding method and a computer program product. In a first aspect of the present disclosure, there is provided a driver arranged to be connected to a Battery Management System, BMS, said BMS comprising a battery, wherein the driver comprises: a voltage control unit arranged to control a voltage provided to said BMS for charging said battery, wherein said voltage provided to said BMS gradually increases to a charging voltage; a current control unit arranged to control a current provided to said BMS wherein said current provided to said battery is set at a safety current value during a time that said voltage gradually increases and is then increased to a nominal current value once said charging voltage has been reached. The present disclosure is directed to a system comprising a driver, for example an emergency driver, and a battery pack. The battery pack comprises a Battery Management System, BMS, arranged for managing and optimizing the performance of a battery. It may perform all kinds of operations to ensure the safe and efficient operation of the battery. The driver in accordance with the present disclosure may be an emergency driver. An emergency driver is a component of a system designed to provide emergency lighting in situations where the primary power source fails. It is typically used in buildings, such as commercial spaces, offices, or residential complexes, to ensure that there is sufficien