PS810 datasheet(15/46 Pages) MICROCHIP

15 / 46 page

DS21904C-page 15

PS810

TABLE 4-2:

VALUE NAMES IN THE MEMORY

4.4.2

COMPENSATING FOR CELL AGING

As lithium ion cells age, the voltage versus capacity

curves become depressed. That is, the battery cell can

no longer deliver as high of a voltage as it once could

for a given capacity. The overall capacity loss is

adjusted for by the relearning of full charge capacity.

The End-Of-Discharge voltage points, which are

voltage points at which a certain capacity remains, are

adjusted using a scaling factor.

The End-Of-Discharge voltage points will become lower

with each cycle. A cycle is defined as a total amount of

discharge capacity equal to full charge capacity. Cycle

count is used to determine the age of the cells and the

parameter, AgeFactor, determines the number of milli-

volts that the voltage becomes depressed per cycle.

AgeFactor is subtracted from the End-Of-Discharge

voltage for every cycle the battery has been through.

AgeFactor units are in eighths of millivolts. Thus, with

the effect of aging, the actual End-Of-Discharge voltage

becomes:

EQUATION 4-2:

TEOD(1)

TEOD(2)

TEOD(3)

TEOD(4)

TEOD(5)

TEOD(6)

TEOD(7)

CEOD(1)

VEOD1(1)

VEOD1(2)

VEOD1(3)

VEOD1(4)

VEOD1(5)

VEOD1(6)

VEOD1(7)

VEOD1(8)

CEOD(2)

VEOD2(1)

VEOD2(2)

VEOD2(3)

VEOD2(4)

VEOD2(5)

VEOD2(6)

VEOD2(7)

VEOD2(8)

CEOD(3)

VEOD3(1)

VEOD3(2)

VEOD3(3)

VEOD3(4)

VEOD3(5)

VEOD3(6)

VEOD3(7)

VEOD3(8)

CEOD(4)

VEOD4(1)

VEOD4(2)

VEOD4(3)

VEOD4(4)

VEOD4(5)

VEOD4(6)

VEOD4(7)

VEOD4(8)

CEOD(5)

VEOD5(1)

VEOD5(2)

VEOD5(3)

VEOD5(4)

VEOD5(5)

VEOD5(6)

VEOD5(7)

VEOD5(8)

CEOD(6)

VEOD6(1)

VEOD6(2)

VEOD6(3)

VEOD6(4)

VEOD6(5)

VEOD6(6)

VEOD6(7)

VEOD6(8)

CEOD(7)

VEOD7(1)

VEOD7(2)

VEOD7(3)

VEOD7(4)

VEOD7(5)

VEOD7(6)

VEOD7(7)

VEOD7(8)

CEOD(7)

VEOD8(1)

VEOD8(2)

VEOD8(3)

VEOD8(4)

VEOD8(5)

VEOD8(6)

VEOD8(7)

VEOD8(8)

FCCP(1)

FCCP(2)

FCCP(3)

FCCP(4)

FCCP(5)

FCCP(6)

FCCP(7)

FCCP(8)

VEODaged = VEOD – (CycleCount * AgeFactor * 0.125) mV

PS810 Datasheet(PDF) 15 Page - Microchip Technology

PS810 Datasheet(HTML) 15 Page - Microchip Technology

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46

Datasheet Download

Link URL