1

Nat

iona

l Aer

onau

tics

and

Spac

e Ad

min

istra

tion

ww

w.n

asa.

gov

An

Upd

ate

on th

e Li

thiu

m-Io

n C

ell

Low

-Ear

th-O

rbit

Verif

icat

ion

Test

Pro

gram

20

06

NA

SA A

eros

pace

Bat

tery

Wor

ksh

opH

olid

ay I

nn

Res

earc

h P

ark

Hu

nts

ville

, AL

Nov

14

-16

, 200

6

Con

cha

M. R

eid,

Mic

hel

le A

. Man

zo, T

hom

as B

. Mill

er, a

nd

Bar

bara

I. M

cKis

sock

NAS

A G

lenn

Res

earc

h Ce

nter

Clev

elan

d, O

H

Will

iam

Ben

net

tAS

RC A

eros

pace

Co.

Clev

elan

d, O

H

https://ntrs.nasa.gov/search.jsp?R=20070022412 2020-05-18T02:20:56+00:00Z

An

Upd

ate

on th

e Li

thiu

m-Io

n C

ell L

ow-E

arth

-Orb

it Ve

rific

atio

n Te

st P

rogr

am

A L

ithiu

m-Io

n C

ell L

ow-E

arth

-Orb

it V

erifi

catio

n Te

st P

rogr

am is

bei

ng c

ondu

cted

by

NA

SA

Gle

nn R

esea

rch

Cen

ter t

o as

sess

the

perfo

rman

ce o

f lith

ium

-ion

(Li-i

on) c

ells

ove

r a w

ide

rang

e of

low

-Ear

th-o

rbit

(LE

O) c

ondi

tions

. The

dat

a ge

nera

ted

will

be

used

to

build

an

empi

rical

mod

el fo

r Li-i

on b

atte

ries.

The

goa

l of t

he m

odel

ing

will

be

to d

evel

op a

tool

to p

redi

ct th

e pe

rform

ance

and

cyc

le

life

of L

i-ion

bat

terie

s op

erat

ing

at a

spe

cifie

d se

t of m

issi

on c

ondi

tions

. Usi

ng th

is to

ol, m

issi

on p

lann

ers

will

be a

ble

to d

esig

n op

erat

ion

poin

ts o

f the

bat

tery

sys

tem

whi

le fa

ctor

ing

in m

issi

on re

quire

men

ts a

nd th

e ex

pect

ed li

fe a

nd p

erfo

rman

ce o

f the

bat

terie

s.

Test

con

ditio

ns fo

r the

pro

gram

wer

e se

lect

ed v

ia a

sta

tistic

al d

esig

n of

exp

erim

ents

to s

pan

a ra

nge

of fe

asib

le o

pera

tiona

l co

nditi

ons

for L

EO

aer

ospa

ce a

pplic

atio

ns. T

he v

aria

bles

und

er e

valu

atio

n ar

e te

mpe

ratu

re, d

epth

-of-d

isch

arge

(DO

D),

and

end-

of-

char

ge v

olta

ge (E

OC

V).

The

base

line

mat

rix w

as fo

rmed

by

gene

ratin

g co

mbi

natio

ns fr

om a

set

of t

hree

val

ues

for e

ach

varia

ble.

Te

mpe

ratu

re v

alue

s ar

e 10

°C

, 20

°C a

nd 3

0 °C

. D

epth

-of-d

isch

arge

val

ues

are

20%

, 30%

and

40%

. EO

CV

val

ues

are

3.85

V, 3

.95

V, a

nd 4

.05

V. T

est c

ondi

tions

for i

ndiv

idua

l cel

ls m

ay v

ary

slig

htly

from

the

base

line

test

mat

rix d

epen

ding

upo

n th

e ce

ll m

anuf

actu

rer’s

reco

mm

ende

d op

erat

ing

cond

ition

s. C

ells

from

eac

h ve

ndor

are

bei

ng e

valu

ated

at e

ach

of te

n se

ts o

f tes

t co

nditi

ons.

C

ells

from

four

cel

l man

ufac

ture

rs a

re u

nder

goin

g lif

e cy

cle

test

s. L

ife c

yclin

g on

the

first

set

s of

cel

ls b

egan

in S

epte

mbe

r 200

4.

Thes

e ce

lls c

onsi

st o

f Saf

t 40

ampe

re-h

our (

Ah)

cel

ls a

nd L

ithio

n 30

Ah

cells

. The

se c

ells

hav

e ac

hiev

ed o

ver 1

0,00

0 cy

cles

eac

h,

equi

vale

nt to

abo

ut 2

0 m

onth

s in

LE

O. I

n th

e pa

st y

ear,

the

test

pro

gram

has

exp

ande

d to

incl

ude

the

eval

uatio

n of

Min

e S

afet

y A

pplia

nces

(MS

A) 5

0 A

h ce

lls a

nd A

BS

L ba

ttery

mod

ules

. The

MS

A c

ells

will

beg

in li

fe c

yclin

g in

Oct

ober

200

6. T

he A

BS

L ba

ttery

m

odul

es c

onsi

st o

f com

mer

cial

Son

y ha

rd c

arbo

n 18

650

lithi

um-io

n ce

lls c

onfig

ured

in s

erie

s an

d pa

ralle

l com

bina

tions

to c

reat

e no

min

al 1

4.4

volt,

3 A

h pa

cks

(4s-

2p).

Thes

e m

odul

es h

ave

accu

mul

ated

app

roxi

mat

ely

3000

cyc

les.

R

esul

ts o

n th

e pe

rform

ance

of t

he c

ells

and

mod

ules

will

be

pres

ente

d in

this

pap

er.

The

life

pred

ictio

n an

d pe

rform

ance

mod

el fo

r Li

-ion

cells

in L

EO

will

be

built

by

anal

yzin

g th

e da

ta s

tatis

tical

ly a

nd p

erfo

rmin

g re

gres

sion

ana

lysi

s. C

ells

are

bei

ng c

ycle

d to

failu

re

so th

at d

iffer

ence

s in

per

form

ance

tren

ds th

at o

ccur

at d

iffer

ent s

tage

s in

the

life

of th

e ce

ll ca

n be

obs

erve

d an

d ac

cura

tely

mod

eled

. C

ell t

estin

g is

bei

ng p

erfo

rmed

at t

he N

aval

Sur

face

War

fare

Cen

ter i

n C

rane

, IN

.

2

Nat

iona

l Aer

onau

tics

and

Spac

e Ad

min

istra

tion

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w.n

asa.

gov

Lith

ium

-Ion

LEO

Ver

ific

atio

n T

est

Pro

gram

•In

itiat

ed in

200

2•

Flex

ible

pro

gram

for

the

ass

essm

ent

of L

i-Ion

tec

hnol

ogy

capa

bilit

ies

for

Low

Ear

th O

rbit

–Pr

ovid

e in

form

atio

n ab

out

mul

tiple

ven

dors

–Pr

ovid

e fo

r as

sess

men

t of

tec

hnol

ogy

deve

lopm

ents

•St

atis

tical

Des

ign

of E

xper

imen

ts a

ppro

ach

addr

esse

s pr

ogra

m

test

goa

ls a

nd r

esou

rce

limita

tions

•D

ata

will

be

used

to

deve

lop

an e

mpi

rical

mod

el t

o pr

edic

t lif

e of

ce

lls a

s a

func

tion

of D

OD

, tem

pera

ture

, and

EO

CV•

Test

ing

is c

ondu

cted

at

the

NSW

C in

Cra

ne, I

N

Rep

rese

ntat

ive

prod

ucts

from

eac

h ve

ndor

. Lef

t to

Rig

ht: A

BSL

mod

ules

, Saf

tcel

l, Li

thio

nce

ll, M

SA c

ells

3

Nat

iona

l Aer

onau

tics

and

Spac

e Ad

min

istra

tion

ww

w.n

asa.

gov

Test

Art

icle

s•

40 L

ithio

n (3

0 Ah

) ce

lls–

INCP

95/

28/1

54–

Del

iver

ed 4

/02

•40

Saf

t (4

0 Ah

) ce

lls–

G4

chem

istr

y sp

ace

cells

(H

E542

45)

–D

eliv

ered

4/0

2

•40

MSA

(50

Ah)

cel

ls

–50

G01

–D

eliv

ered

10/

05

•20

4s-

2p m

odul

es w

ith 1

.5 A

h So

ny h

ard

carb

on 1

8650

cel

ls

from

ABS

L–

4S-2

P-SS

TB–

Del

iver

ed 7

/05

4

Nat

iona

l Aer

onau

tics

and

Spac

e Ad

min

istra

tion

ww

w.n

asa.

gov

Test

Set

-up

Saft

, Lith

ion

and

MSA

cel

ls•

Four

cel

ls a

re t

este

d at

eac

h se

t of

co

nditi

ons

•Ce

lls a

re c

onne

cted

in s

erie

s, h

owev

er

the

char

ging

of

each

cel

l is

cont

rolle

d in

divi

dual

ly w

ith t

he u

se o

f ch

arge

co

ntro

l ele

ctro

nics

•

Cells

at

each

tes

t co

nditi

on a

re

indi

vidu

ally

pac

kage

d an

d ho

used

in

the

sam

e ch

ambe

r•

Tem

pera

ture

is m

onito

red

on e

ach

cell

ABSL

mod

ules

•2

ABSL

mod

ules

con

nect

ed in

par

alle

l ar

e te

sted

at

each

con

ditio

n•

Indi

vidu

al c

ell v

olta

ges

are

mon

itore

d•

Char

ging

and

dis

char

ging

is c

ontr

olle

d at

the

mod

ule

com

bina

tion

leve

l•

Tem

pera

ture

is m

onito

red

on e

ach

mod

ule

5

Nat

iona

l Aer

onau

tics

and

Spac

e Ad

min

istra

tion

ww

w.n

asa.

gov

Ch

arac

teri

zati

on a

nd

Test

ing

•Ac

cept

ance

Tes

ting

•Ch

arac

teriz

atio

n Te

stin

g•

Actu

al C

apac

ity D

eter

min

atio

n•

Self-

Dis

char

ge R

ate

•Ca

paci

ty a

t LE

O t

est

cond

ition

s•

LEO

Life

Cyc

ling

–Ch

arge

and

dis

char

ge r

ates

ar

e ca

lcul

ated

usi

ng t

he

aver

age

actu

al d

isch

arge

ca

paci

ty o

f th

e ce

lls a

t 20

°C

•O

pera

tiona

l cap

acity

che

cks

LEO

Tes

t M

atri

x

Tem

p(°C

)En

d-of

-Ch

arge

V

olta

ge/c

ell (

V)

DoD

(%)

304.

053 /

4.04

20

303.

8520

103.

8520

303.

9530

203.

9520

103.

8540

1 /35

2

203.

8530

303.

8540

1 /35

2

204.

053 /

4.04

401 /

352

104.

053 /

4.04

30

1 –

All v

endo

rs e

xcep

t Sa

ft3

–Al

l ven

dors

exc

ept

MSA

2 -

Saft

4 -

MSA

6

Nat

iona

l Aer

onau

tics

and

Spac

e Ad

min

istra

tion

ww

w.n

asa.

gov

Act

ual C

apac

ity D

eter

min

atio

n P

roce

dure

Test

Tem

pera

ture

(°C

)20

Cha

rge

Cut

off V

olta

ge (V

)M

anuf

actu

rer’

s Rec

omm

ende

d V

olta

geSa

ft, L

ithio

n-4

.1, M

SA -

4.0,

AB

SL -

4.2

(use

d 4.

1)D

isch

arge

Cut

off V

olta

ge (V

)3.

0

Sequ

ence

Stab

ilize

to 2

0°C

Star

t with

C =

nam

epla

teC

/2 d

isch

arge

to 3

VC

/5 c

harg

e to

reco

mm

ende

d cu

t-off

vol

tage

Cla

mp,

tape

r to

C/5

0O

pen

Circ

uit f

or 6

0 m

inut

esC

/2 d

isch

arge

to 3

V-c

apac

ity fr

om th

is st

ep

beco

mes

C v

alue

Rep

eat c

yclin

g un

til c

hang

e in

cap

acity

from

C/2

di

scha

rge

step

s ≤1%

7

Nat

iona

l Aer

onau

tics

and

Spac

e Ad

min

istra

tion

ww

w.n

asa.

gov

Saft

and

Lith

ion

Cells

•LE

O t

estin

g st

arte

d in

Sep

tem

ber

2004

•Ce

lls h

ave

accu

mul

ated

app

roxi

mat

ely

1100

0 cy

cles

MSA

Cel

ls•

Char

acte

rizat

ion

test

ing

com

plet

e•

LEO

cyc

ling

will

beg

in in

Nov

embe

r 20

06

ABSL

Mod

ules

•LE

O c

yclin

g be

gan

in A

pril

2006

•M

odul

es h

ave

com

plet

ed a

ppro

xim

atel

y 28

00 c

ycle

s

Test

ing

Stat

us a

s of

Oct

ober

200

6

8

Nat

iona

l Aer

onau

tics

and

Spac

e Ad

min

istra

tion

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w.n

asa.

gov

Res

ult

s of

Cap

acit

y C

har

acte

riza

tion

•Ca

paci

ty r

esul

ts f

or e

ach

vend

or a

t te

mpe

ratu

res

of -

30 °

C, -

10 °

C, 0

°C,

10

°C, 2

0 °C

, 30 °C

, 40 °C

, 50 °C

(Sa

ftan

d M

SA c

ells

wou

ld n

ot c

ycle

at

-30 °C

)•

Capa

city

is m

easu

red

at C

/2 a

nd 2

0° C

from

4.1

V t

o 3.

0 V

(fro

m 4

.0 V

to

3.0

V fo

r M

SA c

ells

). C

ells

are

cha

rged

at

C/5

for

capa

city

cha

ract

eriz

atio

n.•

ABSL

cap

acity

res

ults

are

for

tw

o pa

ralle

l mod

ules

(fo

ur p

aral

lel s

trin

gs)

Aver

age

Capa

city

at

20 °

CSa

ft:

45.

9 Ah

Lith

ion:

32

.7 A

hM

SA:

66.4

Ah

ABSL

:

4.3

1 Ah

Capacity

(°C

)

9

Nat

iona

l Aer

onau

tics

and

Spac

e Ad

min

istra

tion

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w.n

asa.

gov

Saft

En

d-of

-Dis

char

ge V

olta

ges

vers

us

Cyc

les

as a

Fu

nct

ion

of

Tem

pera

ture

End-of-Discharge Voltage (V)

10

Nat

iona

l Aer

onau

tics

and

Spac

e Ad

min

istra

tion

ww

w.n

asa.

gov

Lith

ion

En

d-of

-Dis

char

ge V

olta

ges

vers

us

Cyc

les

as a

Fu

nct

ion

of

Tem

pera

ture

End-of-Discharge Voltage (V)

11

Nat

iona

l Aer

onau

tics

and

Spac

e Ad

min

istra

tion

ww

w.n

asa.

gov

Saft

Cap

acit

ies

at T

est

Con

diti

ons

to 3

.0 V

ver

sus

Cyc

les

as a

Fu

nct

ion

of

Tem

pera

ture

Capacity (Ah)

12

Nat

iona

l Aer

onau

tics

and

Spac

e Ad

min

istra

tion

ww

w.n

asa.

gov

Lith

ion

Cap

acit

ies

at T

est

Con

diti

ons

to 3

.0 V

ver

sus

Cyc

les

as a

Fu

nct

ion

of

Tem

pera

ture

Capacity (Ah)

13

Nat

iona

l Aer

onau

tics

and

Spac

e Ad

min

istra

tion

ww

w.n

asa.

gov

Com

paris

on o

f Spe

cific

Ene

rgy

and

EO

DV

ve

rsus

Cyc

les

Tren

ds

Lith

ion

Pac

k at

Tes

t Con

ditio

ns 2

0 °C

, 20%

DO

D a

nd 3

.95

V E

OC

V

Spe

cific

Ene

rgy

(Wh/

kg)

E

OD

V (V

)

14

Nat

iona

l Aer

onau

tics

and

Spac

e Ad

min

istra

tion

ww

w.n

asa.

gov

Com

paris

on o

f Spe

cific

Ene

rgy

and

EO

DV

ve

rsus

Cyc

les

Tren

ds

Saf

tPac

k at

Tes

t Con

ditio

ns 2

0 °C

, 20%

DO

D a

nd 3

.95

V E

OC

V

Spe

cific

Ene

rgy

(Wh/

kg)

E

OD

V (V

)

15

Nat

iona

l Aer

onau

tics

and

Spac

e Ad

min

istra

tion

ww

w.n

asa.

gov

Com

paris

on o

f Spe

cific

Ene

rgy

vers

us C

ycle

s fo

r Lith

ion

and

Saf

tP

acks

at T

est C

ondi

tions

20

°C, 2

0% D

OD

and

3.9

5 V

EO

CV

Lith

ion

Saf

t

16

Nat

iona

l Aer

onau

tics

and

Spac

e Ad

min

istra

tion

ww

w.n

asa.

gov

Com

paris

on o

f Spe

cific

Ene

rgy

and

EO

DV

ve

rsus

Cyc

les

Tren

ds

Lith

ion

Pac

k at

Tes

t Con

ditio

ns 1

0 °C

, 30%

DO

D a

nd 4

.05

V E

OC

V

Spe

cific

Ene

rgy

(Wh/

kg)

E

OD

V (V

)

17

Nat

iona

l Aer

onau

tics

and

Spac

e Ad

min

istra

tion

ww

w.n

asa.

gov

Com

paris

on o

f Spe

cific

Ene

rgy

and

EO

DV

ve

rsus

Cyc

les

Tren

ds

Saf

tPac

k at

Tes

t Con

ditio

ns 1

0 °C

, 30%

DO

D a

nd 4

.05

V E

OC

V

Spe

cific

Ene

rgy

(Wh/

kg)

E

OD

V (V

)

18

Nat

iona

l Aer

onau

tics

and

Spac

e Ad

min

istra

tion

ww

w.n

asa.

gov

Com

paris

on o

f Spe

cific

Ene

rgy

vers

us C

ycle

s fo

r Lith

ion

and

Saf

t

Pac

ks a

t Tes

t Con

ditio

ns 1

0 °C

, 30%

DO

D a

nd 4

.05

V E

OC

V

Lith

ion

Saf

t

19

Nat

iona

l Aer

onau

tics

and

Spac

e Ad

min

istra

tion

ww

w.n

asa.

gov

•A

cel

l is

cons

ider

ed fa

iled

if its

EO

DV

falls

bel

ow 3

.0 V

dur

ing

LEO

cyc

ling.

•S

ix c

ells

hav

e co

mpl

eted

thei

r life

cyc

ling

by c

yclin

g to

failu

re.

•A

ll fa

ilure

s oc

curr

ed in

cel

ls o

pera

ting

at th

e lo

wes

t EO

CV

and

the

high

est

DO

D fo

r eac

h ve

ndor

.–

Five

of t

he s

ix fa

ilure

s w

ere

in c

ells

ope

ratin

g at

the

low

est t

empe

ratu

re, 1

0 °C

.–

The

sixt

h fa

iled

cell

was

ope

ratin

g at

30

°C.

–Fi

ve o

f the

cel

ls w

ere

Lith

ion

cells

, inc

ludi

ng th

e ce

ll cy

clin

g at

30

°C.

The

sixt

h ce

ll w

as a

Saf

tcel

l.

Prel

imin

ary

stat

istic

al m

odel

s th

at in

corp

orat

e ea

rly f

ailu

re d

ata

are

bein

g bu

ilt

Saft

and

Lith

ion

Failu

re S

umm

ary

20

Nat

iona

l Aer

onau

tics

and

Spac

e Ad

min

istra

tion

ww

w.n

asa.

gov

Saft

and

Lith

ion

Failu

re S

umm

ary

Ven

dor

Tem

p (°

C)

End-

of-C

har

ge

Vol

tage

/cel

l (V

)D

oD(%

)N

um

ber

of

failu

res

404

Lith

ion

303.

8540

168

00

135

Nu

mbe

r of

cyc

les

ach

ieve

d be

fore

fa

ilure

Lith

ion

103.

8590

0 (1

), 31

00 (3

)

Saf

t10

3.85

8400

21

Nat

iona

l Aer

onau

tics

and

Spac

e Ad

min

istra

tion

ww

w.n

asa.

gov

•S

afta

nd L

ithio

nce

lls h

ave

achi

eved

ove

r 11,

000

cycl

es e

ach,

equ

ival

ent t

o ab

out 2

2 m

onth

s in

LE

O.

•S

aftc

ells

gen

eral

ly h

ave

a hi

gher

end

-of-d

isch

arge

vol

tage

(EO

DV

) tha

n Li

thio

nce

lls o

pera

ting

at th

e sa

me

cond

ition

s.

•S

aftc

ells

hav

e a

low

er E

OD

V d

ispe

rsio

n am

ong

cells

ope

ratin

g at

the

sam

e co

nditi

ons

than

Lith

ion

cells

. •

For b

oth

vend

ors,

whe

n ce

lls a

re o

pera

ting

at th

e hi

ghes

t DO

D, t

he E

OD

V o

f th

e ce

lls v

arie

s m

ore

than

the

EO

DV

for t

he c

ells

ope

ratin

g at

the

low

er

DO

Ds.

•

As

a ce

ll’s

EO

DV

get

s lo

wer

and

low

er, o

pera

tiona

l cap

acity

che

cks

tend

toha

ve a

mor

e pr

ofou

nd re

cond

ition

ing

effe

ct o

n th

e ce

ll.

Sum

mar

y -C

ompa

rison

of S

afta

nd L

ithio

nR

esul

ts

22

Nat

iona

l Aer

onau

tics

and

Spac

e Ad

min

istra

tion

ww

w.n

asa.

gov

•M

SA

cel

ls w

ill be

gin

life

cycl

ing

in N

ovem

ber 2

006.

•

Act

ual c

apac

ity d

eter

min

atio

n, o

pen

circ

uit v

olta

ge s

tand

, and

cap

acity

ch

arac

teriz

atio

n at

diff

eren

t tem

pera

ture

s is

com

plet

e.

•A

BS

L m

odul

es h

ave

accu

mul

ated

app

roxi

mat

ely

2800

cyc

les.

•

Issu

es h

ave

aris

en re

gard

ing

test

con

ditio

ns.

•Te

st c

ondi

tions

are

bei

ng re

eval

uate

d.

Sum

mar

y of

MS

A C

ells

and

AB

SL

Mod

ules