<s>
A	O
rechargeable	B-Algorithm
alkaline	I-Algorithm
battery	I-Algorithm
,	O
also	O
known	O
as	O
alkaline	O
rechargeable	B-Architecture
or	O
rechargeable	B-Algorithm
alkaline	I-Algorithm
manganese	I-Algorithm
(	O
RAM	O
)	O
,	O
is	O
a	O
type	O
of	O
alkaline	B-Algorithm
battery	I-Algorithm
that	O
is	O
capable	O
of	O
recharging	B-Architecture
for	O
repeated	O
use	O
.	O
</s>
<s>
The	O
formats	O
include	O
AAA	B-Algorithm
,	O
AA	B-Algorithm
,	O
C	B-Algorithm
,	O
D	B-Algorithm
,	O
and	O
snap-on	O
9-volt	B-Algorithm
batteries	I-Algorithm
.	O
</s>
<s>
Rechargeable	B-Algorithm
alkaline	I-Algorithm
batteries	I-Algorithm
are	O
manufactured	O
fully	O
charged	O
and	O
have	O
the	O
ability	O
to	O
hold	O
their	O
charge	O
for	O
years	O
,	O
longer	O
than	O
NiCd	O
and	O
NiMH	B-Device
batteries	I-Device
,	O
which	O
self-discharge	B-Algorithm
.	O
</s>
<s>
Rechargeable	B-Algorithm
alkaline	I-Algorithm
batteries	I-Algorithm
can	O
have	O
a	O
high	O
recharging	B-Architecture
efficiency	O
and	O
have	O
less	O
environmental	O
impact	O
than	O
disposable	O
cells	O
.	O
</s>
<s>
The	O
first	O
generation	O
rechargeable	B-Algorithm
alkaline	I-Algorithm
batteries	I-Algorithm
were	O
introduced	O
by	O
Union	O
Carbide	O
and	O
Mallory	O
in	O
the	O
early	O
1970s	O
.	O
</s>
<s>
Rechargeable	B-Architecture
alkaline	B-Algorithm
cells	I-Algorithm
are	O
constructed	O
very	O
similarly	O
to	O
disposable	O
alkaline	B-Algorithm
cells	I-Algorithm
.	O
</s>
<s>
Features	O
of	O
the	O
rechargeable	B-Architecture
alkaline	O
that	O
differ	O
from	O
a	O
disposable	O
alkaline	B-Algorithm
cell	I-Algorithm
include	O
:	O
</s>
<s>
The	O
cathode	O
also	O
has	O
a	O
catalyst	O
to	O
recombine	O
any	O
hydrogen	O
that	O
forms	O
;	O
hydrogen	O
is	O
produced	O
as	O
the	O
fine	O
zinc	O
grains	O
created	O
during	O
recharge	B-Architecture
are	O
corroded	O
by	O
the	O
electrolyte	O
.	O
</s>
<s>
Although	O
these	O
batteries	O
can	O
be	O
used	O
in	O
any	O
device	O
that	O
supports	O
a	O
standard	O
size	O
(	O
AA	B-Algorithm
,	O
AAA	B-Algorithm
,	O
C	B-Algorithm
,	O
D	B-Algorithm
,	O
etc	O
.	O
</s>
<s>
If	O
they	O
are	O
discharged	O
by	O
less	O
than	O
25%	O
,	O
they	O
can	O
be	O
recharged	O
for	O
hundreds	O
of	O
cycles	B-Algorithm
to	O
about	O
1.42V	O
.	O
</s>
<s>
If	O
they	O
are	O
discharged	O
by	O
less	O
than	O
50%	O
,	O
they	O
can	O
be	O
almost	O
fully	O
recharged	O
for	O
a	O
few	O
dozen	O
cycles	B-Algorithm
,	O
to	O
about	O
1.32V	O
.	O
</s>
<s>
After	O
a	O
deep	O
discharge	O
,	O
they	O
can	O
be	O
brought	O
to	O
their	O
original	O
high-capacity	O
charge	O
only	O
after	O
a	O
few	O
charge-discharge	O
cycles	B-Algorithm
.	O
</s>
<s>
Manufacturers	O
do	O
not	O
support	O
recharging	B-Architecture
of	O
disposable	O
alkaline	B-Algorithm
batteries	I-Algorithm
,	O
and	O
warn	O
that	O
it	O
may	O
be	O
dangerous	O
.	O
</s>
<s>
Despite	O
this	O
advice	O
,	O
alkaline	B-Algorithm
batteries	I-Algorithm
have	O
been	O
recharged	O
,	O
and	O
chargers	O
have	O
been	O
available	O
.	O
</s>
<s>
The	O
capacity	O
of	O
a	O
recharged	O
alkaline	B-Algorithm
battery	I-Algorithm
declines	O
with	O
number	O
of	O
recharges	B-Architecture
,	O
until	O
it	O
becomes	O
unusable	O
after	O
typically	O
about	O
ten	O
cycles	B-Algorithm
.	O
</s>
<s>
Low-ripple	O
direct	O
current	O
is	O
not	O
suitable	O
for	O
charging	O
disposable	O
alkaline	B-Algorithm
batteries	I-Algorithm
;	O
more	O
suitable	O
is	O
a	O
current	O
pulsed	O
at	O
a	O
rate	O
of	O
40	O
to	O
200	O
pulses	O
per	O
second	O
,	O
with	O
an	O
80%	O
duty	O
cycle	O
.	O
</s>
<s>
Fully	O
discharged	O
cells	O
recharge	B-Architecture
less	O
successfully	O
than	O
only	O
partly	O
depleted	O
cells	O
,	O
particularly	O
if	O
they	O
have	O
been	O
stored	O
in	O
a	O
discharged	O
state	O
—	O
battery	O
charger	O
manufacturers	O
do	O
not	O
claim	O
to	O
recharge	B-Architecture
dead	O
cells	O
.	O
</s>
<s>
Attempting	O
to	O
recharge	B-Architecture
a	O
discharged	O
alkaline	B-Algorithm
battery	I-Algorithm
can	O
cause	O
the	O
production	O
of	O
gas	O
within	O
the	O
sealed	O
canister	O
;	O
pressure	O
generated	O
by	O
rapid	O
accumulation	O
of	O
gas	O
can	O
open	O
the	O
pressure-relief	O
seal	O
and	O
cause	O
leakage	O
of	O
electrolyte	O
.	O
</s>
<s>
As	O
an	O
alkaline	B-Algorithm
battery	I-Algorithm
is	O
discharged	O
,	O
chemicals	O
inside	O
the	O
battery	O
react	O
to	O
create	O
an	O
electric	O
current	O
.	O
</s>
<s>
The	O
reactions	O
used	O
in	O
most	O
alkaline	B-Algorithm
batteries	I-Algorithm
fall	O
into	O
the	O
latter	O
category	O
.	O
</s>
<s>
The	O
rechargeable	B-Algorithm
alkaline	I-Algorithm
battery	I-Algorithm
was	O
,	O
at	O
one	O
time	O
,	O
cheaper	O
than	O
other	O
rechargeable	B-Architecture
types	O
.	O
</s>
<s>
Their	O
capacity	O
is	O
about	O
2/3	O
that	O
of	O
primary	B-Algorithm
cells	I-Algorithm
.	O
</s>
<s>
Cells	O
have	O
a	O
limited	O
cycle	B-Algorithm
life	I-Algorithm
,	O
which	O
is	O
affected	O
by	O
deep	O
discharge	O
;	O
the	O
first	O
cycle	O
gives	O
the	O
greatest	O
capacity	O
,	O
and	O
if	O
deeply	O
discharged	O
a	O
cell	O
may	O
provide	O
only	O
20	O
cycles	B-Algorithm
.	O
</s>
<s>
Like	O
primary	O
alkaline	B-Algorithm
cells	I-Algorithm
,	O
they	O
have	O
a	O
relatively	O
high	O
internal	O
resistance	O
,	O
making	O
them	O
unsuitable	O
for	O
high	O
discharge	O
current	O
(	O
for	O
example	O
,	O
discharging	O
their	O
full	O
capacity	O
in	O
one	O
hour	O
)	O
.	O
</s>
<s>
Unlike	O
rechargeable	B-Algorithm
alkaline	I-Algorithm
batteries	I-Algorithm
,	O
NiMH	B-Device
batteries	I-Device
can	O
endure	O
anywhere	O
from	O
a	O
few	O
hundred	O
to	O
a	O
thousand	O
(	O
or	O
more	O
)	O
deep	O
discharge	O
cycles	B-Algorithm
,	O
resulting	O
in	O
a	O
long	O
useful	O
life	O
;	O
their	O
limitation	O
is	O
now	O
more	O
usually	O
by	O
age	O
rather	O
than	O
cycles	B-Algorithm
.	O
</s>
<s>
Capacity	O
of	O
NiMH	B-Device
batteries	I-Device
is	O
close	O
to	O
that	O
of	O
alkaline	B-Algorithm
batteries	I-Algorithm
.	O
</s>
<s>
Unlike	O
all	O
alkaline	B-Algorithm
batteries	I-Algorithm
(	O
rechargeable	B-Architecture
or	O
otherwise	O
)	O
,	O
internal	O
resistance	O
is	O
low	O
.	O
</s>
<s>
Self-discharge	B-Algorithm
rates	O
are	O
comparable	O
,	O
at	O
least	O
up	O
to	O
six	O
months	O
.	O
</s>
<s>
Rechargeable	B-Algorithm
alkaline	I-Algorithm
batteries	I-Algorithm
produce	O
a	O
voltage	O
of	O
about	O
1.5V	O
,	O
compared	O
with	O
NiCd	O
and	O
NiMH	B-Device
batteries	I-Device
which	O
produce	O
about	O
1.2V	O
.	O
</s>
<s>
In	O
cases	O
where	O
resistance	O
is	O
not	O
strongly	O
dependent	O
on	O
voltage	O
or	O
current	O
,	O
since	O
power	O
varies	O
as	O
the	O
square	O
of	O
voltage	O
,	O
rechargeable	B-Algorithm
alkaline	I-Algorithm
batteries	I-Algorithm
provide	O
about	O
50%	O
more	O
power	O
.	O
</s>
<s>
For	O
example	O
,	O
incandescent	O
lamps	O
are	O
much	O
brighter	O
when	O
powered	O
by	O
rechargeable	B-Architecture
alkaline	O
than	O
by	O
NiCd	O
or	O
NiMH	B-Device
batteries	I-Device
.	O
</s>
<s>
Rechargeable	B-Algorithm
alkaline	I-Algorithm
batteries	I-Algorithm
are	O
developed	O
from	O
primary	O
alkaline	B-Algorithm
batteries	I-Algorithm
,	O
designed	O
to	O
resist	O
leakage	O
that	O
a	O
recharge	B-Architecture
could	O
cause	O
,	O
so	O
they	O
can	O
be	O
safely	O
recharged	O
many	O
times	O
.	O
</s>
<s>
According	O
to	O
the	O
websites	O
of	O
EnviroCell	O
,	O
PureEnergy	O
and	O
old	O
Rayovac	O
packaging	O
,	O
these	O
manufacturers	O
 '	O
rechargeable	B-Algorithm
alkaline	I-Algorithm
batteries	I-Algorithm
have	O
no	O
mercury	O
or	O
cadmium	O
.	O
</s>
