Bilevel equalizer for battery cell charge management
US11139661B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Oct 31, 2019 |
| Grant date | Oct 5, 2021 |
| Priority date | — |
| Expiry date | Jan 30, 2040 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02M3/158
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An equalizer circuit provides both passive and active cell voltage equalization in a battery pack to improve charge and discharge capacity at a low cost. The equalizer circuit is a bilevel circuit that uses both passive equalizers and active equalizers to balance cell voltage. The cells may be grouped into size limited sections which are balanced by passive equalizers. The sections are balanced by active equalizers to promote increased pack charge and discharge capacity. The equalizer circuit can use a current detector or a voltage controlled oscillator to assist in closed loop current control to reduce switching losses and permit use of smaller transistors. The equalizer circuit can use open line protection with capacitors to store excess charge and prevent voltage overload of the switching devices.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.