September 2011 97
Red Scholefield | redscho@The Battery Clinic bellsouth.net
Predict your battery’s performance
A single A123 cell serves well in a Skil
screwdriver.
Left: Hobby chargers can be used for
cordless shop tools.
Five dead Ni -Cds are replaced by a
2S2200 Li-Poly cell in a Dremel tool.
HOBBY CHARGERS for Your Power
Tools; a reader’s email prompted this one:
“I have a Firestorm 12-volt drill. I swear,
every time I need to drill with the cordless,
it’s dead and I end up dragging out the 120-
volt one and an extension cord.
“The Firestorm takes three hours to
charge and the charger unit does not have an
anti-overcharge feature so it will cook a
battery. Anyway, I was thinking, since we
(RC enthusiasts) have all these really
advanced computer chargers, could we also
charge our tools and other things with them?
“Is anyone else using their RC chargers
for other things besides RC?”
My hobby chargers do a good job of
getting a quick charge. Marrying your
cordless device only takes a little
imagination. You can make a charging
interface using the original charger for the
device by gutting it and adding banana plug
leads to mate with your hobby chargers.
Figure 1 shows a number of such
conversions. One is for a 12-volt Skil drill
battery, another uses a U-shaped wood block
with brass contacts and a Makita drill
battery. Even our common clothespins can
be used by adding a couple of spring
contacts to match the battery.
This does not eliminate the annoying
dead-battery problem common with Ni-Cd
and NiMH. This is when our lithium
technology, with its low self-discharge,
comes to the rescue. Just replace whatever
battery was in the device with Li-Poly or
A123—whichever you can make fit—to
come up with a voltage close to that of the
original pack.
Upgrade Those Old, Cordless Power Tools
in Your Shop. A Skil screwdriver allows a
single A123 cell to fit in the handle when
its two-cell Ni-Cd pack is removed. Some
of the sleeve must be cut away on the A123
so it matches the contacts inside the
handle. Then, cut off a section from the
original battery pack to hold it in place.
I had to remove some plastic to allow a
2S Li-Poly pack to replace five Ni-Cd cells
in a cordless Dremel tool. While the
voltage came out slightly higher, the
Dremel accommodated it quite nicely.
When using multicell packs, don’t forget
to bring out a balance connector for
charging.
My 12-volt pack for the Skil drill took
slightly more work. There was no room to
replace the 10 NiCd, so I made room. I
added to the bottom of the pack using
some hardwood and aircraft plywood to
accommodate another pair of A123 cells to
accompany the two that fit into the original
case. I added black paint and some rubber
“feet,” and now I have a pack that is
always ready.
Another conversion is a Dremel 770.
When the six-cell AA Ni-Cd battery pack
failed, I discovered a Li-Poly 960 mAh
would fit nicely into the cavity. The
original pack was 7.2 volts, so two Li-
Polys was a good match. I added a simple
slide switch to replace the complicated
integrated switch. To finish, I made a
plywood box with 1/8-inch aircraft plywood
and epoxied it to the body of the Dremel
770.
My most recent power tool modification
was performed on a Makita 4.8-volt drill.
This little drill is ideal for modeling
purposes, and built like a Mercedes. The
short Cs Ni-Cd was 7 years old and likely
the third replacement.
I found that a 2S2000 Li-Poly pack with
the outer sleeve removed fits perfectly in the
handle where the four C cells had been. The
Also included in this column:
• Hobby chargers
• Power tool upgrade
• Battery testing
• Gas, but no flame
• Pie-in-the-sky advertising
09sig4.QXD_00MSTRPG.QXD 7/22/11 11:25 AM Page 97
98 MODEL AVIATION
A 12-volt Skil drill has been upgraded
with A123 cells.
The Mini Dremel tool gets a Li-Poly power pack. A Makita drill is brought back to life.
label on the drill indicated it was a 4.8-volt
unit and the voltage would be too high.
However, I had a 7.2-volt Master Airscrew
motor that with some minor Dremel work
on the rear support pad, fit nicely.
I removed the spur gear from the
original motor and pressed it on the Master
Airscrew motor with the same shaft size. I
searched the Internet for the Mabuchi RS-
550SH motor and found that it was actually
rated for 4.8 to 12 volts, so I could have
used it.
When modifying any power tool you
have to bring out the balance tap. I use
Cellpro 4s chargers since I don’t need the
power leads for charging. If you use another
charger, then connect the power leads to the
original charge jack and create an adapter
compatible with your charger. The tool can
be used at any time since the self-discharge
rate of lithium is very low.
The test of time. By testing batteries we gain
insight into early performances by using
equipment such as the Computerized Battery
Analyzer III (CBA), which gives us a plot of
the discharge.
Few of us have the resources to do life
testing on packs, so we must rely on the
experience of others who have used the
battery. However, technology is constantly
changing and patterns vary.
What we began tracking on a battery
performance becomes invalid as the
technology changes faster than our
accumulation of data. Here is what I have
found on the packs I have been “testing” by
simply flying them and then collecting
capacity data.
One interesting pack is the Sanyo eneloop
NiMH. I obtained mine from Hangtime
Hobbies in July 2009 and have used it in my
Futaba 9C radio system, and later in my 7C
when I converted to 2.4 GHz.
I am fortunate that I can fly year-round in
Florida, so batteries get a decent workout
flying three days a week. I was surprised
when I conducted a discharge test on the
eneloop pack. There was no change in the
capacity in two years. I recommend buying
this pack when you are ready to replace your
existing one.
A PowerEdge Li-Poly 3S 2,200 mAh I
began using in July 2009 had an initial
capacity of 2,194 mAh discharged at 450
mA. Discharged in April, 2011 at 3 mA, it
gave a respectable 1,999 mAh. This pack has
22 cycles on it and some minor swelling.
An OKHobby Buffalo Li-Poly 3S3200
had an initial capacity of 3,140 mAh in
August 2010. In April 2011, after 36 cycles,
the capacity was 3,010 mAh. Both discharges
were at 3.2 amps, and there was no swelling.
A TrueRC 3S2500 transmitter pack, used
solely for backup, gave nearly the rated
capacity when I first received it in February
2009. It was stored in my battery refrigerator.
I noticed it was extremely swollen and
decided to test it again. I gave it a full charge
with a Cellpro 4s (I have several) and then
discharged it at the 150 mAh transmitter
simulated load on the CBA. It gave only 396
mAh. Charge and discharge were repeated
on a different Cellpro 4s with the same
results. This one was bad.
Note that none of these packs were
driven to the low-voltage ESC cutoff; all
were charged and balanced with the
Cellpro chargers and none were discharged
higher than 10C.
We can draw no definitive conclusions
from tests only on one pack; only that these
packs behaved as indicated under the use
pattern and tests regimes.
This swelling or puffing of Li-Polys is
still somewhat of a mystery. No one has
come up with a clear definition of what is
happening or which gases are generated.
The gasses are believed to be flammable so
I decided to check that out with the swollen
TrueRC pack. Taking the proper safety
precautions, I held a match next to the pack
and made a small incision with a number
11 X-Acto blade and squeezed the cell to
force out any gases. I did this on each cell
and nothing happened. Maybe different
gasses are generated by different kinds of
pack abuse. Overcharge gives you one
kind, deep-discharge another, and just
normal use something else.
One would think as long as we have
been using Li-Polys that someone would
have come forward and shed some light on
this mystery. Should you use a swollen or
puffed pack? Some say to throw it away
immediately (particularly those who are in
the business of selling packs); others say to
continue to use them as long as they
continue to perform. I follow the latter, but
I store swollen packs in a fireproof
container.
Pie-in-the-Sky Department: It seems as
though these are hitting us with increasing
frequency. One recently touted the
world’s smallest petrol engine. One
statement caught my eye: “At present,
charging an ordinary battery to deliver one
unit of energy involves putting 2,000 units
into it.” The article went on to state, “The
engines got so hot they burned themselves
out and could not be reused.” I guess this
09sig4.QXD_00MSTRPG.QXD 7/22/11 11:26 AM Page 98
one isn’t ready for prime time.
Another startup company, Envia, may be
a bit closer to reality with a new siliconcarbon
nano-composite cathode design,
which could result in batteries that can store
twice the amount possible with current
lithium-ion technology. This initiative is
being funded by the United States
Advanced Battery Consortium (a coalition
between Chrysler, Ford, and General
Motors). It might be one to watch.
Keep those cards and letters coming; I need
all the motivation I can get. No email
connection? Then, drop me a note at the
address listed below. MA
Sources:
Red Scholefield
12219 NW 9th Ln.
Newberry FL 32669
www.hangtimes.com/redsbatteryclinic.html
FMA Direct/Revolectrix (Cellpro chargers)
(800) 343-2934
www.fmadirect.com
www.revolectrix.com
West Mountain Radio (CBA III)
(262) 522-6503
www.westmountainradio.com
Sanyo eneloop
www.eneloop.info
PowerEdge
(813) 765-0124
www.poweredgerc.com
OKHobby
[email protected]
www.okhobby.com
TrueRC
(773) 203-8695
www.truerc.com
Envia Systems Inc.
(510) 509-1367
www.enviasystems.com
Edition: Model Aviation - 2011/09
Page Numbers: 97,98,99
Edition: Model Aviation - 2011/09
Page Numbers: 97,98,99
September 2011 97
Red Scholefield | redscho@The Battery Clinic bellsouth.net
Predict your battery’s performance
A single A123 cell serves well in a Skil
screwdriver.
Left: Hobby chargers can be used for
cordless shop tools.
Five dead Ni -Cds are replaced by a
2S2200 Li-Poly cell in a Dremel tool.
HOBBY CHARGERS for Your Power
Tools; a reader’s email prompted this one:
“I have a Firestorm 12-volt drill. I swear,
every time I need to drill with the cordless,
it’s dead and I end up dragging out the 120-
volt one and an extension cord.
“The Firestorm takes three hours to
charge and the charger unit does not have an
anti-overcharge feature so it will cook a
battery. Anyway, I was thinking, since we
(RC enthusiasts) have all these really
advanced computer chargers, could we also
charge our tools and other things with them?
“Is anyone else using their RC chargers
for other things besides RC?”
My hobby chargers do a good job of
getting a quick charge. Marrying your
cordless device only takes a little
imagination. You can make a charging
interface using the original charger for the
device by gutting it and adding banana plug
leads to mate with your hobby chargers.
Figure 1 shows a number of such
conversions. One is for a 12-volt Skil drill
battery, another uses a U-shaped wood block
with brass contacts and a Makita drill
battery. Even our common clothespins can
be used by adding a couple of spring
contacts to match the battery.
This does not eliminate the annoying
dead-battery problem common with Ni-Cd
and NiMH. This is when our lithium
technology, with its low self-discharge,
comes to the rescue. Just replace whatever
battery was in the device with Li-Poly or
A123—whichever you can make fit—to
come up with a voltage close to that of the
original pack.
Upgrade Those Old, Cordless Power Tools
in Your Shop. A Skil screwdriver allows a
single A123 cell to fit in the handle when
its two-cell Ni-Cd pack is removed. Some
of the sleeve must be cut away on the A123
so it matches the contacts inside the
handle. Then, cut off a section from the
original battery pack to hold it in place.
I had to remove some plastic to allow a
2S Li-Poly pack to replace five Ni-Cd cells
in a cordless Dremel tool. While the
voltage came out slightly higher, the
Dremel accommodated it quite nicely.
When using multicell packs, don’t forget
to bring out a balance connector for
charging.
My 12-volt pack for the Skil drill took
slightly more work. There was no room to
replace the 10 NiCd, so I made room. I
added to the bottom of the pack using
some hardwood and aircraft plywood to
accommodate another pair of A123 cells to
accompany the two that fit into the original
case. I added black paint and some rubber
“feet,” and now I have a pack that is
always ready.
Another conversion is a Dremel 770.
When the six-cell AA Ni-Cd battery pack
failed, I discovered a Li-Poly 960 mAh
would fit nicely into the cavity. The
original pack was 7.2 volts, so two Li-
Polys was a good match. I added a simple
slide switch to replace the complicated
integrated switch. To finish, I made a
plywood box with 1/8-inch aircraft plywood
and epoxied it to the body of the Dremel
770.
My most recent power tool modification
was performed on a Makita 4.8-volt drill.
This little drill is ideal for modeling
purposes, and built like a Mercedes. The
short Cs Ni-Cd was 7 years old and likely
the third replacement.
I found that a 2S2000 Li-Poly pack with
the outer sleeve removed fits perfectly in the
handle where the four C cells had been. The
Also included in this column:
• Hobby chargers
• Power tool upgrade
• Battery testing
• Gas, but no flame
• Pie-in-the-sky advertising
09sig4.QXD_00MSTRPG.QXD 7/22/11 11:25 AM Page 97
98 MODEL AVIATION
A 12-volt Skil drill has been upgraded
with A123 cells.
The Mini Dremel tool gets a Li-Poly power pack. A Makita drill is brought back to life.
label on the drill indicated it was a 4.8-volt
unit and the voltage would be too high.
However, I had a 7.2-volt Master Airscrew
motor that with some minor Dremel work
on the rear support pad, fit nicely.
I removed the spur gear from the
original motor and pressed it on the Master
Airscrew motor with the same shaft size. I
searched the Internet for the Mabuchi RS-
550SH motor and found that it was actually
rated for 4.8 to 12 volts, so I could have
used it.
When modifying any power tool you
have to bring out the balance tap. I use
Cellpro 4s chargers since I don’t need the
power leads for charging. If you use another
charger, then connect the power leads to the
original charge jack and create an adapter
compatible with your charger. The tool can
be used at any time since the self-discharge
rate of lithium is very low.
The test of time. By testing batteries we gain
insight into early performances by using
equipment such as the Computerized Battery
Analyzer III (CBA), which gives us a plot of
the discharge.
Few of us have the resources to do life
testing on packs, so we must rely on the
experience of others who have used the
battery. However, technology is constantly
changing and patterns vary.
What we began tracking on a battery
performance becomes invalid as the
technology changes faster than our
accumulation of data. Here is what I have
found on the packs I have been “testing” by
simply flying them and then collecting
capacity data.
One interesting pack is the Sanyo eneloop
NiMH. I obtained mine from Hangtime
Hobbies in July 2009 and have used it in my
Futaba 9C radio system, and later in my 7C
when I converted to 2.4 GHz.
I am fortunate that I can fly year-round in
Florida, so batteries get a decent workout
flying three days a week. I was surprised
when I conducted a discharge test on the
eneloop pack. There was no change in the
capacity in two years. I recommend buying
this pack when you are ready to replace your
existing one.
A PowerEdge Li-Poly 3S 2,200 mAh I
began using in July 2009 had an initial
capacity of 2,194 mAh discharged at 450
mA. Discharged in April, 2011 at 3 mA, it
gave a respectable 1,999 mAh. This pack has
22 cycles on it and some minor swelling.
An OKHobby Buffalo Li-Poly 3S3200
had an initial capacity of 3,140 mAh in
August 2010. In April 2011, after 36 cycles,
the capacity was 3,010 mAh. Both discharges
were at 3.2 amps, and there was no swelling.
A TrueRC 3S2500 transmitter pack, used
solely for backup, gave nearly the rated
capacity when I first received it in February
2009. It was stored in my battery refrigerator.
I noticed it was extremely swollen and
decided to test it again. I gave it a full charge
with a Cellpro 4s (I have several) and then
discharged it at the 150 mAh transmitter
simulated load on the CBA. It gave only 396
mAh. Charge and discharge were repeated
on a different Cellpro 4s with the same
results. This one was bad.
Note that none of these packs were
driven to the low-voltage ESC cutoff; all
were charged and balanced with the
Cellpro chargers and none were discharged
higher than 10C.
We can draw no definitive conclusions
from tests only on one pack; only that these
packs behaved as indicated under the use
pattern and tests regimes.
This swelling or puffing of Li-Polys is
still somewhat of a mystery. No one has
come up with a clear definition of what is
happening or which gases are generated.
The gasses are believed to be flammable so
I decided to check that out with the swollen
TrueRC pack. Taking the proper safety
precautions, I held a match next to the pack
and made a small incision with a number
11 X-Acto blade and squeezed the cell to
force out any gases. I did this on each cell
and nothing happened. Maybe different
gasses are generated by different kinds of
pack abuse. Overcharge gives you one
kind, deep-discharge another, and just
normal use something else.
One would think as long as we have
been using Li-Polys that someone would
have come forward and shed some light on
this mystery. Should you use a swollen or
puffed pack? Some say to throw it away
immediately (particularly those who are in
the business of selling packs); others say to
continue to use them as long as they
continue to perform. I follow the latter, but
I store swollen packs in a fireproof
container.
Pie-in-the-Sky Department: It seems as
though these are hitting us with increasing
frequency. One recently touted the
world’s smallest petrol engine. One
statement caught my eye: “At present,
charging an ordinary battery to deliver one
unit of energy involves putting 2,000 units
into it.” The article went on to state, “The
engines got so hot they burned themselves
out and could not be reused.” I guess this
09sig4.QXD_00MSTRPG.QXD 7/22/11 11:26 AM Page 98
one isn’t ready for prime time.
Another startup company, Envia, may be
a bit closer to reality with a new siliconcarbon
nano-composite cathode design,
which could result in batteries that can store
twice the amount possible with current
lithium-ion technology. This initiative is
being funded by the United States
Advanced Battery Consortium (a coalition
between Chrysler, Ford, and General
Motors). It might be one to watch.
Keep those cards and letters coming; I need
all the motivation I can get. No email
connection? Then, drop me a note at the
address listed below. MA
Sources:
Red Scholefield
12219 NW 9th Ln.
Newberry FL 32669
www.hangtimes.com/redsbatteryclinic.html
FMA Direct/Revolectrix (Cellpro chargers)
(800) 343-2934
www.fmadirect.com
www.revolectrix.com
West Mountain Radio (CBA III)
(262) 522-6503
www.westmountainradio.com
Sanyo eneloop
www.eneloop.info
PowerEdge
(813) 765-0124
www.poweredgerc.com
OKHobby
[email protected]
www.okhobby.com
TrueRC
(773) 203-8695
www.truerc.com
Envia Systems Inc.
(510) 509-1367
www.enviasystems.com
Edition: Model Aviation - 2011/09
Page Numbers: 97,98,99
September 2011 97
Red Scholefield | redscho@The Battery Clinic bellsouth.net
Predict your battery’s performance
A single A123 cell serves well in a Skil
screwdriver.
Left: Hobby chargers can be used for
cordless shop tools.
Five dead Ni -Cds are replaced by a
2S2200 Li-Poly cell in a Dremel tool.
HOBBY CHARGERS for Your Power
Tools; a reader’s email prompted this one:
“I have a Firestorm 12-volt drill. I swear,
every time I need to drill with the cordless,
it’s dead and I end up dragging out the 120-
volt one and an extension cord.
“The Firestorm takes three hours to
charge and the charger unit does not have an
anti-overcharge feature so it will cook a
battery. Anyway, I was thinking, since we
(RC enthusiasts) have all these really
advanced computer chargers, could we also
charge our tools and other things with them?
“Is anyone else using their RC chargers
for other things besides RC?”
My hobby chargers do a good job of
getting a quick charge. Marrying your
cordless device only takes a little
imagination. You can make a charging
interface using the original charger for the
device by gutting it and adding banana plug
leads to mate with your hobby chargers.
Figure 1 shows a number of such
conversions. One is for a 12-volt Skil drill
battery, another uses a U-shaped wood block
with brass contacts and a Makita drill
battery. Even our common clothespins can
be used by adding a couple of spring
contacts to match the battery.
This does not eliminate the annoying
dead-battery problem common with Ni-Cd
and NiMH. This is when our lithium
technology, with its low self-discharge,
comes to the rescue. Just replace whatever
battery was in the device with Li-Poly or
A123—whichever you can make fit—to
come up with a voltage close to that of the
original pack.
Upgrade Those Old, Cordless Power Tools
in Your Shop. A Skil screwdriver allows a
single A123 cell to fit in the handle when
its two-cell Ni-Cd pack is removed. Some
of the sleeve must be cut away on the A123
so it matches the contacts inside the
handle. Then, cut off a section from the
original battery pack to hold it in place.
I had to remove some plastic to allow a
2S Li-Poly pack to replace five Ni-Cd cells
in a cordless Dremel tool. While the
voltage came out slightly higher, the
Dremel accommodated it quite nicely.
When using multicell packs, don’t forget
to bring out a balance connector for
charging.
My 12-volt pack for the Skil drill took
slightly more work. There was no room to
replace the 10 NiCd, so I made room. I
added to the bottom of the pack using
some hardwood and aircraft plywood to
accommodate another pair of A123 cells to
accompany the two that fit into the original
case. I added black paint and some rubber
“feet,” and now I have a pack that is
always ready.
Another conversion is a Dremel 770.
When the six-cell AA Ni-Cd battery pack
failed, I discovered a Li-Poly 960 mAh
would fit nicely into the cavity. The
original pack was 7.2 volts, so two Li-
Polys was a good match. I added a simple
slide switch to replace the complicated
integrated switch. To finish, I made a
plywood box with 1/8-inch aircraft plywood
and epoxied it to the body of the Dremel
770.
My most recent power tool modification
was performed on a Makita 4.8-volt drill.
This little drill is ideal for modeling
purposes, and built like a Mercedes. The
short Cs Ni-Cd was 7 years old and likely
the third replacement.
I found that a 2S2000 Li-Poly pack with
the outer sleeve removed fits perfectly in the
handle where the four C cells had been. The
Also included in this column:
• Hobby chargers
• Power tool upgrade
• Battery testing
• Gas, but no flame
• Pie-in-the-sky advertising
09sig4.QXD_00MSTRPG.QXD 7/22/11 11:25 AM Page 97
98 MODEL AVIATION
A 12-volt Skil drill has been upgraded
with A123 cells.
The Mini Dremel tool gets a Li-Poly power pack. A Makita drill is brought back to life.
label on the drill indicated it was a 4.8-volt
unit and the voltage would be too high.
However, I had a 7.2-volt Master Airscrew
motor that with some minor Dremel work
on the rear support pad, fit nicely.
I removed the spur gear from the
original motor and pressed it on the Master
Airscrew motor with the same shaft size. I
searched the Internet for the Mabuchi RS-
550SH motor and found that it was actually
rated for 4.8 to 12 volts, so I could have
used it.
When modifying any power tool you
have to bring out the balance tap. I use
Cellpro 4s chargers since I don’t need the
power leads for charging. If you use another
charger, then connect the power leads to the
original charge jack and create an adapter
compatible with your charger. The tool can
be used at any time since the self-discharge
rate of lithium is very low.
The test of time. By testing batteries we gain
insight into early performances by using
equipment such as the Computerized Battery
Analyzer III (CBA), which gives us a plot of
the discharge.
Few of us have the resources to do life
testing on packs, so we must rely on the
experience of others who have used the
battery. However, technology is constantly
changing and patterns vary.
What we began tracking on a battery
performance becomes invalid as the
technology changes faster than our
accumulation of data. Here is what I have
found on the packs I have been “testing” by
simply flying them and then collecting
capacity data.
One interesting pack is the Sanyo eneloop
NiMH. I obtained mine from Hangtime
Hobbies in July 2009 and have used it in my
Futaba 9C radio system, and later in my 7C
when I converted to 2.4 GHz.
I am fortunate that I can fly year-round in
Florida, so batteries get a decent workout
flying three days a week. I was surprised
when I conducted a discharge test on the
eneloop pack. There was no change in the
capacity in two years. I recommend buying
this pack when you are ready to replace your
existing one.
A PowerEdge Li-Poly 3S 2,200 mAh I
began using in July 2009 had an initial
capacity of 2,194 mAh discharged at 450
mA. Discharged in April, 2011 at 3 mA, it
gave a respectable 1,999 mAh. This pack has
22 cycles on it and some minor swelling.
An OKHobby Buffalo Li-Poly 3S3200
had an initial capacity of 3,140 mAh in
August 2010. In April 2011, after 36 cycles,
the capacity was 3,010 mAh. Both discharges
were at 3.2 amps, and there was no swelling.
A TrueRC 3S2500 transmitter pack, used
solely for backup, gave nearly the rated
capacity when I first received it in February
2009. It was stored in my battery refrigerator.
I noticed it was extremely swollen and
decided to test it again. I gave it a full charge
with a Cellpro 4s (I have several) and then
discharged it at the 150 mAh transmitter
simulated load on the CBA. It gave only 396
mAh. Charge and discharge were repeated
on a different Cellpro 4s with the same
results. This one was bad.
Note that none of these packs were
driven to the low-voltage ESC cutoff; all
were charged and balanced with the
Cellpro chargers and none were discharged
higher than 10C.
We can draw no definitive conclusions
from tests only on one pack; only that these
packs behaved as indicated under the use
pattern and tests regimes.
This swelling or puffing of Li-Polys is
still somewhat of a mystery. No one has
come up with a clear definition of what is
happening or which gases are generated.
The gasses are believed to be flammable so
I decided to check that out with the swollen
TrueRC pack. Taking the proper safety
precautions, I held a match next to the pack
and made a small incision with a number
11 X-Acto blade and squeezed the cell to
force out any gases. I did this on each cell
and nothing happened. Maybe different
gasses are generated by different kinds of
pack abuse. Overcharge gives you one
kind, deep-discharge another, and just
normal use something else.
One would think as long as we have
been using Li-Polys that someone would
have come forward and shed some light on
this mystery. Should you use a swollen or
puffed pack? Some say to throw it away
immediately (particularly those who are in
the business of selling packs); others say to
continue to use them as long as they
continue to perform. I follow the latter, but
I store swollen packs in a fireproof
container.
Pie-in-the-Sky Department: It seems as
though these are hitting us with increasing
frequency. One recently touted the
world’s smallest petrol engine. One
statement caught my eye: “At present,
charging an ordinary battery to deliver one
unit of energy involves putting 2,000 units
into it.” The article went on to state, “The
engines got so hot they burned themselves
out and could not be reused.” I guess this
09sig4.QXD_00MSTRPG.QXD 7/22/11 11:26 AM Page 98
one isn’t ready for prime time.
Another startup company, Envia, may be
a bit closer to reality with a new siliconcarbon
nano-composite cathode design,
which could result in batteries that can store
twice the amount possible with current
lithium-ion technology. This initiative is
being funded by the United States
Advanced Battery Consortium (a coalition
between Chrysler, Ford, and General
Motors). It might be one to watch.
Keep those cards and letters coming; I need
all the motivation I can get. No email
connection? Then, drop me a note at the
address listed below. MA
Sources:
Red Scholefield
12219 NW 9th Ln.
Newberry FL 32669
www.hangtimes.com/redsbatteryclinic.html
FMA Direct/Revolectrix (Cellpro chargers)
(800) 343-2934
www.fmadirect.com
www.revolectrix.com
West Mountain Radio (CBA III)
(262) 522-6503
www.westmountainradio.com
Sanyo eneloop
www.eneloop.info
PowerEdge
(813) 765-0124
www.poweredgerc.com
OKHobby
[email protected]
www.okhobby.com
TrueRC
(773) 203-8695
www.truerc.com
Envia Systems Inc.
(510) 509-1367
www.enviasystems.com