Patent · US Expired

Apparatus for measuring internal resistance of wet cell storage batteries having non-removable cell caps

US5047722A · kind A · utility

207Cited by
5References
5Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 17, 1989
Grant dateSep 10, 1991
Priority date
Expiry dateApr 17, 2009

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01R31/389
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

Apparatus for measuring the total internal resistance of a multicell battery having positive and negative terminals employs a first transistor device having an input and an output and having mutually exclusive conductive and non-conductive electric states. An arrangement of resistances is connected in series with the device to form a network. The network is connected between the positive and negative terminals. An operational amplifier has an output connected to the input of the device and first and second inputs. The first input is connected to the network at a point connected to both of the device and the arrangement. A square wave signal alternating between a positive voltage and ground on alternate half cycles is applied to the second input. The device is in the conductive state when the alternating voltage is positive and is in the non-conductive state when the alternating voltage is at ground. The network conducts no current when the device is in the non-conductive state and conducts a current of constant value when the device is in the conductive state. The voltage appearing between the terminals as a result of the current in the network is monotonically related to the inter…

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