Battery charging method and apparatus using current control
US5617007A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 17, 1994 |
| Grant date | Apr 1, 1997 |
| Priority date | — |
| Expiry date | Aug 17, 2014 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02E60/10
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A battery charging aparatus and method are provided for charging a battery using current control with a switching power supply charging circuit coupled to the battery. During a first charging phase, a predetermined constant charging current is applied to the battery. The battery voltage is monitored and a second charging phase is started when the battery voltage reaches a predetermined threshold voltage. During a second charging phase, a sequence of stepwise decreasing-amplitude current pulses are applied to the battery. The envelope for the decreasing current pulses is exponential which is characteristic of the current for voltage controlled charging methods. The battery voltage is maintained at a temperature compensated target with a 1% tolerance. The charging current is compared to a predetermined minimum amplitude value and a third charging phase is started when the sequential charging current pulse equals the predetermined minimum amplitude value. During a third charging phase, predetermined charging current pulses having the predetermined minimum amplitude value are applied to the battery. The battery voltage is maintained at a temperature compensated target with a 1% toleran…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.