<s>
Zinc	B-Algorithm
–	I-Algorithm
air	I-Algorithm
batteries	I-Algorithm
(	O
non-rechargeable	O
)	O
,	O
and	O
zinc	B-Algorithm
–	I-Algorithm
air	I-Algorithm
fuel	I-Algorithm
cells	I-Algorithm
(	O
mechanically	O
rechargeable	O
)	O
are	O
metal	B-Architecture
–	I-Architecture
air	I-Architecture
batteries	I-Architecture
powered	O
by	O
oxidizing	O
zinc	B-Application
with	O
oxygen	O
from	O
the	O
air	O
.	O
</s>
<s>
Sizes	O
range	O
from	O
very	O
small	O
button	B-Algorithm
cells	I-Algorithm
for	O
hearing	O
aids	O
,	O
larger	O
batteries	O
used	O
in	O
film	O
cameras	O
that	O
previously	O
used	O
mercury	B-Algorithm
batteries	I-Algorithm
,	O
to	O
very	O
large	O
batteries	O
used	O
for	O
electric	O
vehicle	O
propulsion	O
and	O
grid-scale	O
energy	O
storage	O
.	O
</s>
<s>
During	O
discharge	O
,	O
a	O
mass	O
of	O
zinc	B-Application
particles	O
forms	O
a	O
porous	O
anode	O
,	O
which	O
is	O
saturated	O
with	O
an	O
electrolyte	O
.	O
</s>
<s>
Oxygen	O
from	O
the	O
air	O
reacts	O
at	O
the	O
cathode	O
and	O
forms	O
hydroxyl	O
ions	O
which	O
migrate	O
into	O
the	O
zinc	B-Application
paste	O
and	O
form	O
zincate	O
(	O
)	O
,	O
releasing	O
electrons	O
to	O
travel	O
to	O
the	O
cathode	O
.	O
</s>
<s>
The	O
zincate	O
decays	O
into	O
zinc	B-Application
oxide	O
and	O
water	O
returns	O
to	O
the	O
electrolyte	O
.	O
</s>
<s>
Zinc	B-Algorithm
–	I-Algorithm
air	I-Algorithm
batteries	I-Algorithm
have	O
some	O
properties	O
of	O
fuel	O
cells	O
as	O
well	O
as	O
batteries	O
:	O
the	O
zinc	B-Application
is	O
the	O
fuel	O
,	O
the	O
reaction	O
rate	O
can	O
be	O
controlled	O
by	O
varying	O
the	O
air	O
flow	O
,	O
and	O
oxidized	O
zinc/electrolyte	O
paste	O
can	O
be	O
replaced	O
with	O
fresh	O
paste	O
.	O
</s>
<s>
Zinc	B-Algorithm
–	I-Algorithm
air	I-Algorithm
batteries	I-Algorithm
can	O
be	O
used	O
to	O
replace	O
now	O
discontinued	O
1.35	O
V	O
mercury	B-Algorithm
batteries	I-Algorithm
(	O
although	O
with	O
a	O
significantly	O
shorter	O
operating	O
life	O
)	O
,	O
which	O
in	O
the	O
1970s	O
through	O
1980s	O
were	O
commonly	O
used	O
in	O
photo	O
cameras	O
and	O
hearing	O
aids	O
.	O
</s>
<s>
Possible	O
future	O
applications	O
of	O
this	O
battery	O
include	O
its	O
deployment	O
as	O
an	O
electric	B-Architecture
vehicle	I-Architecture
battery	I-Architecture
and	O
as	O
a	O
utility-scale	O
energy	O
storage	O
system	O
.	O
</s>
<s>
The	O
effect	O
of	O
oxygen	O
was	O
known	O
early	O
in	O
the	O
19th	O
century	O
when	O
wet-cell	O
Leclanche	B-Algorithm
batteries	I-Algorithm
absorbed	O
atmospheric	O
oxygen	O
into	O
the	O
carbon	O
cathode	O
current	O
collector	O
.	O
</s>
<s>
In	O
1878	O
,	O
a	O
porous	O
platinized	B-Operating_System
carbon	O
air	O
electrode	O
was	O
found	O
to	O
work	O
as	O
well	O
as	O
the	O
manganese	O
dioxide	O
(	O
)	O
of	O
the	O
Leclanche	B-Algorithm
cell	I-Algorithm
.	O
</s>
<s>
This	O
type	O
is	O
still	O
used	O
for	O
large	O
zinc	B-Application
–	O
air	O
cells	O
for	O
navigation	O
aids	O
and	O
rail	O
transportation	O
.	O
</s>
<s>
Large	O
primary	O
zinc	B-Application
–	O
air	O
cells	O
such	O
as	O
the	O
Thomas	O
A	O
.	O
Edison	O
Industries	O
Carbonaire	O
type	O
were	O
used	O
for	O
railway	O
signaling	O
,	O
remote	O
communication	O
sites	O
,	O
and	O
navigation	O
buoys	O
.	O
</s>
<s>
Development	O
in	O
the	O
1970s	O
of	O
thin	O
electrodes	O
based	O
on	O
fuel-cell	O
research	O
allowed	O
application	O
to	O
small	O
button	O
and	O
prismatic	O
primary	B-Algorithm
cells	I-Algorithm
for	O
hearing	O
aids	O
,	O
pagers	B-Application
,	O
and	O
medical	O
devices	O
,	O
especially	O
cardiac	O
telemetry	O
.	O
</s>
<s>
The	O
chemical	O
equations	O
for	O
the	O
zinc	B-Application
–	O
air	O
cell	O
are	O
:	O
</s>
<s>
Zinc	B-Algorithm
–	I-Algorithm
air	I-Algorithm
batteries	I-Algorithm
cannot	O
be	O
used	O
in	O
a	O
sealed	O
battery	B-Algorithm
holder	I-Algorithm
since	O
some	O
air	O
must	O
come	O
in	O
;	O
the	O
oxygen	O
in	O
1	O
liter	O
of	O
air	O
is	O
required	O
for	O
every	O
ampere-hour	O
of	O
capacity	O
used	O
.	O
</s>
<s>
Zinc	B-Algorithm
–	I-Algorithm
air	I-Algorithm
batteries	I-Algorithm
have	O
higher	O
energy	O
density	O
than	O
many	O
other	O
types	B-Algorithm
of	I-Algorithm
battery	I-Algorithm
because	O
atmospheric	O
air	O
is	O
one	O
of	O
the	O
battery	O
reactants	O
,	O
in	O
contrast	O
to	O
battery	B-Algorithm
types	I-Algorithm
that	O
require	O
a	O
material	O
such	O
as	O
manganese	O
dioxide	O
in	O
combination	O
with	O
zinc	B-Application
.	O
</s>
<s>
The	O
following	O
table	O
shows	O
the	O
calculation	O
of	O
specific	O
energy	O
for	O
a	O
specific	O
zinc-air	B-Algorithm
battery	I-Algorithm
and	O
several	O
other	O
commonly	O
available	O
batteries	O
of	O
different	O
chemistries	O
.	O
</s>
<s>
Zinc	B-Application
–	O
air	O
cells	O
have	O
long	O
shelf	O
life	O
if	O
sealed	O
to	O
keep	O
air	O
out	O
;	O
even	O
miniature	O
button	B-Algorithm
cells	I-Algorithm
can	O
be	O
stored	O
for	O
up	O
to	O
3	O
years	O
at	O
room	O
temperature	O
with	O
little	O
capacity	O
loss	O
if	O
their	O
seal	O
is	O
not	O
removed	O
.	O
</s>
<s>
The	O
operating	O
life	O
of	O
a	O
zinc	B-Application
–	O
air	O
cell	O
is	O
a	O
critical	O
function	O
of	O
its	O
interaction	O
with	O
its	O
environment	O
.	O
</s>
<s>
Miniature	O
cells	O
have	O
high	O
self-discharge	B-Algorithm
once	O
opened	O
to	O
air	O
;	O
the	O
cell	O
's	O
capacity	O
is	O
intended	O
to	O
be	O
used	O
within	O
a	O
few	O
weeks	O
.	O
</s>
<s>
Button	B-Algorithm
cells	I-Algorithm
have	O
a	O
limited	O
current	O
drain	O
;	O
for	O
example	O
an	O
IEC	O
PR44	B-Algorithm
cell	O
has	O
a	O
capacity	O
of	O
600	O
milliamp-hours	O
(	O
mAh	O
)	O
but	O
a	O
maximum	O
current	O
of	O
only	O
22	O
milliamps	O
(	O
mA	O
)	O
.	O
</s>
<s>
Low	O
temperature	O
reduces	O
primary	B-Algorithm
cell	I-Algorithm
capacity	O
but	O
the	O
effect	O
is	O
small	O
for	O
low	O
drains	O
.	O
</s>
<s>
Large	O
zinc	B-Algorithm
–	I-Algorithm
air	I-Algorithm
batteries	I-Algorithm
,	O
with	O
capacities	O
up	O
to	O
2,000	O
ampere	O
–	O
hours	O
per	O
cell	O
,	O
are	O
used	O
to	O
power	O
navigation	O
instruments	O
and	O
marker	O
lights	O
,	O
oceanographic	O
experiments	O
and	O
railway	O
signals	O
.	O
</s>
<s>
Primary	B-Algorithm
cells	I-Algorithm
are	O
made	O
in	O
button	O
format	O
to	O
about	O
1	O
Ah	O
.	O
</s>
<s>
Button	B-Algorithm
cells	I-Algorithm
are	O
highly	O
effective	O
,	O
but	O
it	O
is	O
difficult	O
to	O
extend	O
the	O
same	O
construction	O
to	O
larger	O
sizes	O
due	O
to	O
air	O
diffusion	O
performance	O
,	O
heat	O
dissipation	O
,	O
and	O
leakage	O
problems	O
.	O
</s>
<s>
Rechargeable	O
zinc	B-Application
–	O
air	O
cells	O
require	O
zinc	B-Application
precipitation	O
from	O
the	O
water-based	O
electrolyte	O
to	O
be	O
closely	O
controlled	O
.	O
</s>
<s>
Challenges	O
include	O
dendrite	O
formation	O
,	O
non-uniform	O
zinc	B-Application
dissolution	O
,	O
and	O
limited	O
solubility	O
in	O
electrolytes	O
.	O
</s>
<s>
Fluidic	B-Algorithm
Energy	I-Algorithm
has	O
apparently	O
covered	O
hundreds	O
of	O
thousands	O
of	O
outages	O
in	O
Asia	O
at	O
distributed	O
critical	O
load	O
sites	O
.	O
</s>
<s>
AZA	O
Battery	O
has	O
announced	O
development	O
of	O
pilot	O
production	O
of	O
prismatic	O
zinc	B-Algorithm
air	I-Algorithm
cells	O
with	O
characteristics	O
suitable	O
for	O
both	O
stationary	O
storage	O
and	O
mobility	O
applications	O
.	O
</s>
<s>
Rechargeable	O
systems	O
may	O
mechanically	O
replace	O
the	O
anode	O
and	O
electrolyte	O
,	O
essentially	O
operating	O
as	O
a	O
refurbishable	O
primary	B-Algorithm
cell	I-Algorithm
,	O
or	O
may	O
use	O
zinc	B-Application
powder	O
or	O
other	O
methods	O
to	O
replenish	O
the	O
reactants	O
.	O
</s>
<s>
However	O
,	O
primary	O
lithium	B-Language
batteries	O
offered	O
higher	O
discharge	O
rates	O
and	O
easier	O
handling	O
.	O
</s>
<s>
Some	O
approaches	O
use	O
a	O
large	O
zinc	B-Algorithm
–	I-Algorithm
air	I-Algorithm
battery	I-Algorithm
to	O
maintain	O
charge	O
on	O
a	O
high	O
discharge	O
–	O
rate	O
battery	O
used	O
for	O
peak	O
loads	O
during	O
acceleration	O
.	O
</s>
<s>
Zinc	B-Application
granules	O
serve	O
as	O
the	O
reactant	O
.	O
</s>
<s>
Vehicles	O
recharge	O
via	O
exchanging	O
used	O
electrolyte	O
and	O
depleted	O
zinc	B-Application
for	O
fresh	O
reactants	O
at	O
a	O
service	O
station	O
.	O
</s>
<s>
The	O
term	O
zinc	B-Algorithm
–	I-Algorithm
air	I-Algorithm
fuel	I-Algorithm
cell	I-Algorithm
usually	O
refers	O
to	O
a	O
zinc	B-Algorithm
–	I-Algorithm
air	I-Algorithm
battery	I-Algorithm
in	O
which	O
zinc	B-Application
metal	O
is	O
added	O
and	O
zinc	B-Application
oxide	O
is	O
removed	O
continuously	O
.	O
</s>
<s>
Zinc	B-Application
electrolyte	O
paste	O
or	O
pellets	O
are	O
pushed	O
into	O
a	O
chamber	O
,	O
and	O
waste	O
zinc	B-Application
oxide	O
is	O
pumped	O
into	O
a	O
waste	O
tank	O
or	O
bladder	O
inside	O
the	O
fuel	O
tank	O
.	O
</s>
<s>
Fresh	O
zinc	B-Application
paste	O
or	O
pellets	O
are	O
taken	O
from	O
the	O
fuel	O
tank	O
.	O
</s>
<s>
The	O
zinc	B-Application
oxide	O
waste	O
is	O
pumped	O
out	O
at	O
a	O
refueling	O
station	O
for	O
recycling	O
.	O
</s>
<s>
Alternatively	O
,	O
this	O
term	O
may	O
refer	O
to	O
an	O
electrochemical	O
system	O
in	O
which	O
zinc	B-Application
is	O
a	O
co-reactant	O
assisting	O
the	O
reformation	O
of	O
hydrocarbons	O
at	O
the	O
anode	O
of	O
a	O
fuel	O
cell	O
.	O
</s>
<s>
Cobalt	O
oxide/carbon	O
nanotube	O
hybrid	O
oxygen	O
reduction	O
catalyst	O
and	O
nickel-iron	O
layered	O
double	O
hydroxide	O
oxygen	O
evolution	O
cathode	O
catalysts	O
exhibited	O
higher	O
catalytic	O
activity	O
and	O
durability	O
in	O
concentrated	O
alkaline	O
electrolytes	O
than	O
precious	O
metal	O
platinum	B-Operating_System
and	O
iridium	O
catalysts	O
.	O
</s>
<s>
The	O
resulting	O
primary	O
zinc	B-Algorithm
–	I-Algorithm
air	I-Algorithm
battery	I-Algorithm
showed	O
peak	O
power	O
density	O
of	O
~	O
265mW/cm3	O
,	O
current	O
density	O
of	O
~	O
200	O
mA/cm3	O
at	O
1	O
V	O
and	O
energy	O
density	O
>700	O
Wh/kg	O
.	O
</s>
<s>
Primary	B-Algorithm
batteries	I-Algorithm
demonstrated	O
an	O
open-circuit	O
potential	O
of	O
1.48	O
V	O
,	O
a	O
specific	O
capacity	O
of	O
735	O
mAh/gr	O
(	O
Zn	O
)	O
(	O
energy	O
density	O
of	O
835	O
Wh/kg	O
(	O
Zn	O
)	O
)	O
,	O
a	O
peak	O
power	O
density	O
of	O
55mW/cm³	O
and	O
stable	O
operation	O
for	O
240	O
h	O
after	O
mechanical	O
recharging	O
.	O
</s>
<s>
Metallic	O
zinc	B-Application
could	O
be	O
used	O
as	O
an	O
alternative	O
fuel	O
for	O
vehicles	O
,	O
either	O
in	O
a	O
zinc	B-Algorithm
–	I-Algorithm
air	I-Algorithm
battery	I-Algorithm
or	O
to	O
generate	O
hydrogen	O
near	O
the	O
point	O
of	O
use	O
.	O
</s>
<s>
Zinc	B-Application
's	O
characteristics	O
have	O
motivated	O
considerable	O
interest	O
as	O
an	O
energy	O
source	O
for	O
electric	O
vehicles	O
.	O
</s>
<s>
Fuel	O
cells	O
using	O
pellets	O
would	O
be	O
able	O
to	O
quickly	O
replace	O
zinc-oxide	O
with	O
fresh	O
zinc	B-Application
metal	O
.	O
</s>
<s>
The	O
zinc	B-Application
–	O
air	O
cell	O
is	O
a	O
primary	B-Algorithm
cell	I-Algorithm
(	O
non-rechargeable	O
)	O
;	O
recycling	O
is	O
required	O
to	O
reclaim	O
the	O
zinc	B-Application
;	O
much	O
more	O
energy	O
is	O
required	O
to	O
reclaim	O
the	O
zinc	B-Application
than	O
is	O
usable	O
in	O
a	O
vehicle	O
.	O
</s>
<s>
One	O
advantage	O
of	O
utilizing	O
zinc	B-Algorithm
–	I-Algorithm
air	I-Algorithm
batteries	I-Algorithm
for	O
vehicle	O
propulsion	O
is	O
the	O
mineral	O
's	O
relative	O
abundance	O
when	O
compared	O
to	O
lithium	B-Language
.	O
</s>
<s>
As	O
of	O
2020	O
,	O
the	O
total	O
global	O
zinc	B-Application
reserves	O
are	O
estimated	O
to	O
be	O
around	O
1.9	O
billion	O
tons	O
,	O
whereas	O
total	O
lithium	B-Language
reserves	O
are	O
estimated	O
as	O
86	O
million	O
tons	O
.	O
</s>
<s>
Con	O
Edison	O
and	O
City	O
University	O
of	O
New	O
York	O
are	O
testing	O
a	O
zinc-based	O
battery	O
from	O
Urban	O
Electric	O
Power	O
as	O
part	O
of	O
a	O
New	O
York	O
State	O
Energy	O
Research	O
and	O
Development	O
Authority	O
program	O
.	O
</s>
<s>
When	O
a	O
load	O
is	O
applied	O
over	O
zinc-air	B-Algorithm
batteries	I-Algorithm
without	O
access	O
to	O
oxygen	O
,	O
they	O
generate	O
hydrogen	O
gas	O
at	O
a	O
fairly	O
controllable	O
rate	O
,	O
proportional	O
to	O
the	O
load	O
.	O
</s>
<s>
Attempts	O
to	O
address	O
air	O
's	O
limitations	O
include	O
:	O
</s>
<s>
Pumping	O
zinc	B-Application
slurry	O
through	O
the	O
battery	O
in	O
one	O
direction	O
for	O
charging	O
and	O
reversing	O
for	O
discharge	O
.	O
</s>
<s>
Zinc	B-Application
corrosion	O
can	O
produce	O
potentially	O
explosive	O
hydrogen	O
.	O
</s>
<s>
Older	O
designs	O
used	O
mercury	O
amalgam	O
amounting	O
to	O
about	O
1%	O
of	O
the	O
weight	O
of	O
a	O
button	B-Algorithm
cell	I-Algorithm
,	O
to	O
prevent	O
zinc	B-Application
corrosion	O
.	O
</s>
<s>
Zinc	B-Application
itself	O
is	O
relatively	O
low	O
in	O
toxicity	O
.	O
</s>
<s>
In	O
United	O
States	O
waters	O
,	O
environmental	O
regulations	O
now	O
require	O
proper	O
disposal	O
of	O
primary	B-Algorithm
batteries	I-Algorithm
removed	O
from	O
navigation	O
aids	O
.	O
</s>
<s>
Formerly	O
,	O
discarded	O
zinc	B-Application
–	O
air	O
primary	B-Algorithm
batteries	I-Algorithm
were	O
dropped	O
into	O
the	O
water	O
around	O
buoys	O
,	O
which	O
allowed	O
mercury	O
to	O
escape	O
into	O
the	O
environment	O
.	O
</s>
