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Charging li-ion batteries

I have a battery pack scrounged from a Dell computer. It is their pn
66WHR rated 14.8V 4460MAH. It is comprised of 8 cells, that is four
sets of two in parallel. Each set measures 3.9V, so therefore each
cell seems to be 3.9V. The cells are Sony Fukushima STG, bearing the
following numbers: US18650GR and STG 6KEO7R. They are all also marked
G5.There were multiple terminals on the connnector on this pack and
also a small circuit board with many smd circuits on it. Perhaps the
charger or regulator? These would make a really nice standby battery
pack for a project, but how would I charge them? I understand that
there is a specific charging protocol for these type of batteries. Is
there a generic charger available to address this? Or can anyone
suggest an alternate method? Thanks, Lenny Stein, Barlen Electronics.
 
M

Meat Plow

Jan 1, 1970
0
I have a battery pack scrounged from a Dell computer. It is their pn
66WHR rated 14.8V 4460MAH. It is comprised of 8 cells, that is four
sets of two in parallel. Each set measures 3.9V, so therefore each
cell seems to be 3.9V. The cells are Sony Fukushima STG, bearing the
following numbers: US18650GR and STG 6KEO7R. They are all also marked
G5.There were multiple terminals on the connnector on this pack and
also a small circuit board with many smd circuits on it. Perhaps the
charger or regulator? These would make a really nice standby battery
pack for a project, but how would I charge them? I understand that
there is a specific charging protocol for these type of batteries. Is
there a generic charger available to address this? Or can anyone
suggest an alternate method? Thanks, Lenny Stein, Barlen Electronics.

One thing you don't want to do is to deal with unknowns when charging LiOn
batteries. Want a good standby 12 volt source? Buy a gel cell.
 
J

James Sweet

Jan 1, 1970
0
I have a battery pack scrounged from a Dell computer. It is their pn
66WHR rated 14.8V 4460MAH. It is comprised of 8 cells, that is four
sets of two in parallel. Each set measures 3.9V, so therefore each
cell seems to be 3.9V. The cells are Sony Fukushima STG, bearing the
following numbers: US18650GR and STG 6KEO7R. They are all also marked
G5.There were multiple terminals on the connnector on this pack and
also a small circuit board with many smd circuits on it. Perhaps the
charger or regulator? These would make a really nice standby battery
pack for a project, but how would I charge them? I understand that
there is a specific charging protocol for these type of batteries. Is
there a generic charger available to address this? Or can anyone
suggest an alternate method? Thanks, Lenny Stein, Barlen Electronics.

You really have to be careful with these things. Have a look at
Dallas/Maxim, TI, and other companies that make power electronics. They'll
have parts to do just this along with detailed application notes. The caveat
is that most of them are tiny surface mount packages, which you may or may
not be up to working with.
 
S

Sam Goldwasser

Jan 1, 1970
0
James Sweet said:
You really have to be careful with these things. Have a look at
Dallas/Maxim, TI, and other companies that make power electronics. They'll
have parts to do just this along with detailed application notes. The caveat
is that most of them are tiny surface mount packages, which you may or may
not be up to working with.

I would REALLY recommend NOT trying to deal with Li Ion charging unless
you are willing to do all the research and design to use parts like those
referenced above and build a smart charger. Some types of Li Ion batteries
may catch fire and explode if not treated properly. I don't know if what
you have falls into that category but you can't just stick them on a constant
voltage or constant current supply safely or expect to get reasonable life
that way.

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header above is
ignored unless my full name AND either lasers or electronics is included in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.
 
I would REALLY recommend NOT trying to deal with Li Ion charging unless
you are willing to do all the research and design to use parts like those
referenced above and build a smart charger. Some types of Li Ion batteries
may catch fire and explode if not treated properly. I don't know if what
you have falls into that category but you can't just stick them on a constant
voltage or constant current supply safely or expect to get reasonable life
that way.

--- sam | Sci.Electronics.Repair FAQ:http://www.repairfaq.org/
Repair | Main Table of Contents:http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ:http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites:http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header above is
ignored unless my full name AND either lasers or electronics is included in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.- Hide quoted text -

- Show quoted text -

Thanks for all the responses. I think I'll just stick with
conventional stuff and give these things the heave ho. Lenny.
 
M

mike

Jan 1, 1970
0
I have a battery pack scrounged from a Dell computer. It is their pn
66WHR rated 14.8V 4460MAH. It is comprised of 8 cells, that is four
sets of two in parallel. Each set measures 3.9V, so therefore each
cell seems to be 3.9V. The cells are Sony Fukushima STG, bearing the
following numbers: US18650GR and STG 6KEO7R. They are all also marked
G5.There were multiple terminals on the connnector on this pack and
also a small circuit board with many smd circuits on it. Perhaps the
charger or regulator? These would make a really nice standby battery
pack for a project, but how would I charge them? I understand that
there is a specific charging protocol for these type of batteries. Is
there a generic charger available to address this? Or can anyone
suggest an alternate method? Thanks, Lenny Stein, Barlen Electronics.
If that's the pack that fits the Dell C-series laptops, you can often
buy dead laptops with a still-working charger. cheap or free.
I used one to charge my dell batteries.

You need to do the research and understand what you're doing to safely
charge lithium batteries...but it can be done.

You can easily burn your house down while putting gasoline in your
lawnmower. I don't have any statistics, but I bet there are MANY more
instances of gasoline fires than lithium fires. Yet we still manage
to put gas in our lawnmowers. People who understand the issues and pay
attention to them don't burn down their houses. Ditto for people
who charge batteries.

Your problem is much simpler if you can live with charging one battery.

And yes, the world is full of idiots and lawyers...so I ain't gonna try
to tell you how.
 
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