Apparatus for preventing over-discharge of battery

Patent metadata

Field	Value
Publication number	US-10879710-B2
Application number	US-201715806657-A
Country	US
Kind code	B2
Filing date	Nov 8, 2017
Priority date	Nov 9, 2016
Publication date	Dec 29, 2020
Grant date	Dec 29, 2020

Abstract

An apparatus for preventing a battery from being over-discharged according to the present invention includes: a latch relay which connects or disconnects the load of the vehicle; a voltage measuring circuit which measures a voltage of the auxiliary battery for every predetermined period when a ignition of the vehicle is off, and compares the measured voltage of the auxiliary battery with one or more over-discharge reference values that serve as references for determining whether the auxiliary battery is over-discharged; and a control unit which turns off the latch relay when the voltage of the auxiliary battery is equal to or less than the over-discharge reference value as a result of the comparison by the voltage measuring circuit, in which the voltage measuring circuit outputs an enable signal for operating the control unit when the voltage of the auxiliary battery is equal to or less than the over-discharge reference value.

First claim

What is claimed is:

1. An apparatus for preventing a battery from being over-discharged, the apparatus comprising:
a latch relay configured to connect or disconnect a load of a vehicle that receives power from an auxiliary battery and is driven;
a voltage measuring circuit configured to measure a voltage of the auxiliary battery and compare the measured voltage of the auxiliary battery with at least one over-discharge reference value that serves as references for determining whether the auxiliary battery is over-discharged;
a control unit configured to turn off the latch relay when the voltage of the auxiliary battery is equal to or less than the over-discharge reference value as a result of the comparison by the voltage measuring circuit;
a power supplying unit configured to supply operation power to the control unit; and
a timer configured to be turned on and set a predetermined period for measuring the voltage of the auxiliary battery when an ignition of the vehicle is off,
wherein the voltage measuring circuit measures the voltage of the auxiliary battery for the predetermined period when the ignition of the vehicle is off and outputs an enable signal for operating the control unit when the voltage of the auxiliary battery is equal to or less than the over-discharge reference value, and
the power supplying unit continuously supplies the operation power to the control unit when the ignition of the vehicle is on, and supplies the operation power to the control unit in response to the enable signal received from the voltage measuring circuit when the ignition of the vehicle is off.

2. The apparatus of claim 1 , wherein the auxiliary battery includes a lithium ion battery.

3. The apparatus of claim 1 , further comprising:
a reference voltage setting device configured to set the over-discharge reference value.

4. The apparatus of claim 3 , wherein the over-discharge reference value includes a first over-discharge reference value that serves as a reference for charging the auxiliary battery and a second over-discharge reference value that serves as a reference for turning off the latch relay.

5. The apparatus of claim 4 , wherein the first over-discharge reference value is higher than the second over-discharge reference value.

6. The apparatus of claim 4 , further comprising:
a charger configured charge the voltage of the auxiliary battery,
wherein when the voltage of the auxiliary battery is higher than the second over-discharge reference value or is equal to or less than the first over-discharge reference value as a result of the comparison by the voltage measuring circuit, the control unit operates the charger.

7. The apparatus of claim 6 , wherein when the vehicle is a vehicle using electric energy, the charger receives power from a main battery that drives a motor of the vehicle and charges the auxiliary battery.

8. The apparatus of claim 1 , wherein when the voltage of the auxiliary battery is equal to or less than the over-discharge reference value, the voltage measuring circuit outputs the enable signal for operating the control unit to the power supplying unit.

9. The apparatus of claim 8 , wherein the control unit stores the voltage of the auxiliary battery measured by the voltage measuring circuit for the every predetermined period.

10. The apparatus of claim 9 , wherein the control unit compares the voltage of the auxiliary battery measured by the voltage measuring circuit with a pre-stored voltage of the auxiliary battery measured in a previous period, and
when a difference between the voltage of the auxiliary battery measured by the voltage measuring circuit and the pre-stored voltage of the auxiliary battery measured in the previous period is a predetermined value or more, the control unit diagnoses that the auxiliary battery has a failure.

11. The apparatus of claim 10 , wherein when the control unit diagnoses that the auxiliary battery has the failure, the control unit warns a user of the failure of the auxiliary battery.

Assignees

• Hyundai Autron Co Ltd

Inventors

• Park Jae Seong

Classifications

• H02J2105/37

  exchanging power with electric vehicles [EV] or with hybrid electric vehicles [HEV] · CPC title

• H02J2105/33

  exchanging power with road vehicles · CPC title

• H02J7/63

  against overdischarge · CPC title

• H02J7/663 Primary

  using battery or load disconnect circuits (H02J9/002 takes precedence) · CPC title

• H02J7/60 Primary

  including safety or protection arrangements · CPC title