# US 5,352,982 A · Method and apparatus for displaying a residual electric charge of a battery for an electrically driven vehicle

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 5,352,982 A
- Document ID: US5352982A
- Status: Granted
- Kind: A
- Application number: 07/767,650
- Filed: 1991-09-30
- Granted: 1994-10-04
- Earliest claimed: 1990-10-16
- Assignees: Honda Giken Kogyo Kabushiki Kaisha
- Inventors: Yoshihiro Nakazawa; Satoshi Honda; Hiroyuki Suzuki; Shigemi Sasaki
- Web page: https://patentgrep.com/patent/US5352982A

## CPC

- G01R 31/3648: {comprising digital calculation means, e.g. for performing an algorithm}
- B60L 1/14: to electric lighting circuits
- B60L 3/0046: {relating to electric energy storage systems, e.g. batteries or capacitors}
- B60L 3/12: Recording operating variables {; Monitoring of operating variables}
- B60L 53/14: Conductive energy transfer
- B60L 58/10: for monitoring or controlling batteries
- G01R 31/3828: using current integration
- B60L 2240/12: Speed
- B60L 2240/421: Speed
- B60L 2240/545: Temperature
- B60L 2240/547: Voltage
- B60L 2240/549: Current
- B60L 2240/80: Time limits
- B60L 2250/10: by alarm
- B60L 2250/16: by display
- B60L 2260/54: Energy consumption estimation
- G01R 31/374: with means for correcting the measurement for temperature or ageing
- Y02T 10/64: Electric machine technologies in electromobility
- Y02T 10/70: Energy storage systems for electromobility, e.g. batteries
- Y02T 10/7072: Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
- Y02T 90/14: Plug-in electric vehicles
- Y10S 320/19: Charger status, e.g. voltmeter
- G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12)
- B60L: PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES (arrangements or mounting of electrical propulsion units or of plural diverse prime-movers for mutual or common propulsion in vehicles B60K1/00, B60K6/20; arrangements or mounting of electrical gearing in vehicles B60K17/12, B60K17/14; preventing wheel slip by reducing power in rail vehicles B61C15/08; dynamo-electric machines H02K; control or regulation of electric motors H02P); SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES (electric coupling devices combined with mechanical couplings of vehicles B60D1/64; electric heating for vehicles B60H1/00); ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL (control or regulation of electric motors H02P); MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
- Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y10S: TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS

## Abstract

In a method and apparatus for displaying a residual electric charge for a battery of an electrically driven vehicle, the battery's capacity is detected after the battery is charged. This information is utilized by a residual electric charge meter to indicate a fully charged state of the battery. As the battery begins to supply current to the electric loads, dissipated power is calculated from the product of the value of the current and the length of time during which the current has been supplied. This calculated dissipated power is subtracted from the fully charged capacity from time to time in order to derive the residual electric charge. The battery residual electric charge meter is driven in accordance with the derived value to indicate a current residual electric charge. As such, the battery residual electric charge meter displays values which depend upon the actual fully charged capacity and a residual charge.

## Claims

### Claim 1

An apparatus for determining a residual electric charge of a battery for an electrically driven vehicle comprising:
measuring means for initially measuring a charge capacity of the battery after completion of a charging operation;
calculation means for calculating power dissipated by the battery;
control means, operatively connected to said measuring means and said calculation means, for determining a residual electric charge of the battery from a difference between the measured charge capacity and the calculated dissipated power; and
display means, operatively connected to said control means, for displaying said residual electric charge of the battery,
said control means comparing said residual electric charge to a predetermined lower limit and disabling power supply from the battery to the electrically driven vehicle when said residual electric charge is lower than said predetermined lower limit.