Minutes of Meeting.

P1568/D

Recommended Practice for Electrical Sizing of Nickel-Cadmium Batteries for Rail Passenger Cars

Place: Saft Nife

Baltimore, MD

Date: September 26, 2000.

Attendees: Jacques Boscher

Jim McDowall

Ted Mavronicolas

Claude Gabriel

Alex Sinyak

Rich Niederberger

Sachit Kakkar

General

The initial draft copy of the standard (P1568/D0.1) was reviewed by the sub-committee, corrections were formulated and direction resolved for missing sections. We were able to address all sections of the standard, and arrive at preliminary concurrence of resolution of problem areas.

Specific Problem Areas Discussed

The state of charge was discussed. The state of charge is the product of AH put in and the charge efficiency. Therefore, the SOC charge should take not only AH into a consideration but also the charge efficiency.

The charge efficiency is a function of temperature. The discussion revolved around how to include the charge efficiency when calculating the state of charge.

A few examples were discussed to explain the situation where it is difficult to mention in the standard the charge efficiency factor for calculation. One example was if a battery is charged at a low temperature, then the battery voltage will reach maximum quickly and the current drawn by the battery will decrease. Even though the charge efficiency at low temperature is high, the SOC will be low because the AH put in are less. In other words, it is difficult to put in the AH at low temperature.

Action Items

Alex Sinyak will develop an updated version of the standard (P1568/D1.X) and distribute it to the sub-committee for a meeting and review in February 2001. It is hopeful that after that meeting we will be in a position to generate a full complete draft standard that can be sent to the full RTVISC committee for a line-by-line review.