Patent · US Expired

Battery cell equalization circuit

US5956241A · kind A · utility

26Cited by
6References
20Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 24, 1996
Grant dateSep 21, 1999
Priority date
Expiry dateDec 24, 2016

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02J7/0024
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A battery power conversion circuit comprising a cell equalization circuit that ensures that each cell in a multiple battery cell stack is depleted of charge at an equal rate. The stack is coupled to provide current to a primary winding of a transformer. Each of the nodes between cells is coupled to the primary winding of the transformer through a transistor such that an equal number of turns of the primary winding are present between each node. An additional transistor coupled in series with the primary winding controls the current through the primary winding such that a capacitor coupled to a secondary winding of the transformer may be charged by an induced secondary current to a desired voltage level for powering a load. A controller circuit monitors the output voltage level and controls the transistor in series with the primary winding for maintaining the desired load voltage through a feedback loop. When the transistor in series with the primary winding is turned on to allow current to flow through the primary winding, each of the transistors coupled to each of the nodes between battery cells is also turned on by the controller. Only a small current travels through each of the …

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.