OESF Portables Forum

Everything Else => Sharp Zaurus => Model Specific Forums => Distros, Development, and Model Specific Forums => Archived Forums => 5x00 Hardware => Topic started by: doug-taylor on October 21, 2005, 12:08:09 pm

Title: External Battery Pack With Sl-5500?
Post by: doug-taylor on October 21, 2005, 12:08:09 pm
I have an SL-5500.  I also have an old Casio Cassiopeia.  The AC adaptors for these two machines are essentially identical, and I have been successfully using the C's adaptor in my 5500 for a week or two.

My question is this:  The Cassiopeia came with an external battery pack which plugs into the AC adaptor plug.  Could I use the external battery pack with my Zaurus?  

It seems like I should be able to, but I thought I'd see if there were any caveats.  I sure don't want to fry my power supply!  The battery pack consists of two 2V/2A (I assume that means "two volt, two amp") batteries, if that tells anyone anything.
Title: External Battery Pack With Sl-5500?
Post by: kwiniarz on October 22, 2005, 07:27:17 pm
it should work as long as it's the same voltage. What i did to mine was, i added an extra battey which i got out of broken Pocket pc. I soldered some thin wire (so i could close the battery lid) to the battery and just taped the thin battey to the back of the zaurus, now i get about 4 hours of life with wifi and full brightness.

There is thread floating around on these forums just do a search
Title: External Battery Pack With Sl-5500?
Post by: arniel on October 24, 2005, 04:49:27 am
Quote
it should work as long as it's the same voltage. What i did to mine was, i added an extra battey which i got out of broken Pocket pc. I soldered some thin wire (so i could close the battery lid) to the battery and just taped the thin battey to the back of the zaurus, now i get about 4 hours of life with wifi and full brightness.

There is thread floating around on these forums just do a search
[div align=\"right\"][a href=\"index.php?act=findpost&pid=100563\"][{POST_SNAPBACK}][/a][/div]

Are you saying that you wired a second batter IN PARALLEL with the existing one?  I always worry about doing that sort of thing in case they behave like NiMH where, if one battery is weak, the other will dump lots of current into it and potentially overheat it.
Title: External Battery Pack With Sl-5500?
Post by: doug-taylor on October 24, 2005, 09:37:50 am
Quote
it should work as long as it's the same voltage. What i did to mine was, i added an extra battey which i got out of broken Pocket pc. I soldered some thin wire (so i could close the battery lid) to the battery and just taped the thin battey to the back of the zaurus, now i get about 4 hours of life with wifi and full brightness.

There is thread floating around on these forums just do a search
[div align=\"right\"][a href=\"index.php?act=findpost&pid=100563\"][{POST_SNAPBACK}][/a][/div]

Thanks.  I may get brave and try it.  :-)
Title: External Battery Pack With Sl-5500?
Post by: kwiniarz on October 24, 2005, 08:16:22 pm
that's right i did it IN PARALLEL, it's been working fine for a couple months now
Title: External Battery Pack With Sl-5500?
Post by: arniel on October 25, 2005, 09:57:29 am
Quote
that's right i did it IN PARALLEL, it's been working fine for a couple months now
[div align=\"right\"][a href=\"index.php?act=findpost&pid=100825\"][{POST_SNAPBACK}][/a][/div]
Cool
I was looking at getting a replacement digital camera battery, 3.7v 1800mAh for £10 but didn't fancy hacking the back of the battery cover to cope with the size.
Title: External Battery Pack With Sl-5500?
Post by: Shdwdrgn on October 25, 2005, 11:44:03 am
The thread is here (https://www.oesf.org/forums/index.php?showtopic=7651) if you want to look through it.  If you want to use a completely external battery pack (plugged into the AC jack), you will need something that puts out 5-6 volts DC.  However if you want to wire up in parallel with the internal battery, you MUST choose a lithium battery pack which is 3.7V and has it's own charging regulator built in.  The advantage of this method is that the normal AC charger will charge both batteries at the same time (obviously requiring longer charging times), and the on-screen battery monitor will accurately show the time remaining for the combination of batteries (if you use an external battery pack, the battery monitor cannot tell how much charge is left in it).

I started that thread just over a year ago, and have been using two lithium battery packs on my Z for the entire time.  There has been no problems with the charging circuits and I still get quite a bit of life out of them.
Title: External Battery Pack With Sl-5500?
Post by: doug-taylor on October 25, 2005, 11:51:50 am
Quote
The thread is here (https://www.oesf.org/forums/index.php?showtopic=7651) if you want to look through it.  If you want to use a completely external battery pack (plugged into the AC jack), you will need something that puts out 5-6 volts DC. 
[div align=\"right\"][a href=\"index.php?act=findpost&pid=100892\"][{POST_SNAPBACK}][/a][/div]

Ah!  Guess I won't try the external battery pack after all, since it's putting out only 4V DC.  Although I could maybe wire another battery in with it.  Hmm . . .

Anyway, thank you very much for the 411.
Title: External Battery Pack With Sl-5500?
Post by: craigtyson on October 25, 2005, 11:57:20 am
Quote
Quote
it should work as long as it's the same voltage. What i did to mine was, i added an extra battey which i got out of broken Pocket pc. I soldered some thin wire (so i could close the battery lid) to the battery and just taped the thin battey to the back of the zaurus, now i get about 4 hours of life with wifi and full brightness.

There is thread floating around on these forums just do a search
[div align=\"right\"][a href=\"index.php?act=findpost&pid=100563\"][{POST_SNAPBACK}][/a][/div]

Are you saying that you wired a second batter IN PARALLEL with the existing one?  I always worry about doing that sort of thing in case they behave like NiMH where, if one battery is weak, the other will dump lots of current into it and potentially overheat it.
[div align=\"right\"][a href=\"index.php?act=findpost&pid=100700\"][{POST_SNAPBACK}][/a][/div]
That's what diodes R 4.  Put a diode on the + of each battery in the parallel circuit and there can be no cross charging
Title: External Battery Pack With Sl-5500?
Post by: Shdwdrgn on October 25, 2005, 01:59:30 pm
Quote
That's what diodes R 4.  Put a diode on the + of each battery in the parallel circuit and there can be no cross charging
The problem with diodes is that they also drop the voltage slightly.  Most of the lithium packs I looked at contained a charging circuit in them which monitors the state of the battery.  This should also (probably?) protect the battery from problems with the other packs.
Title: External Battery Pack With Sl-5500?
Post by: arniel on October 28, 2005, 04:55:28 am
Quote
Quote
That's what diodes R 4.  Put a diode on the + of each battery in the parallel circuit and there can be no cross charging
The problem with diodes is that they also drop the voltage slightly.  Most of the lithium packs I looked at contained a charging circuit in them which monitors the state of the battery.  This should also (probably?) protect the battery from problems with the other packs.
[div align=\"right\"][a href=\"index.php?act=findpost&pid=100909\"][{POST_SNAPBACK}][/a][/div]

Do you connect all three terminals in parallel, or just the + and - terminals?
Title: External Battery Pack With Sl-5500?
Post by: Shdwdrgn on October 28, 2005, 11:19:23 am
Just the + and - are fine.  The third terminal tells the Z that a battery is installed.  You probably won't even have a wire for that on any battery packs you buy.
Title: External Battery Pack With Sl-5500?
Post by: t0xa on May 04, 2006, 06:10:22 am
Hi everyone,

It's seem it's been a while since last post here. Can someone who has used these battery packs share their personal experience?
Title: External Battery Pack With Sl-5500?
Post by: technojunkie on May 12, 2006, 05:42:19 pm
Quote
Hi everyone,

It's seem it's been a while since last post here. Can someone who has used these battery packs share their personal experience?
[div align=\"right\"][a href=\"index.php?act=findpost&pid=125694\"][{POST_SNAPBACK}][/a][/div]

I built a brick that uses 4AA batteries through the charging port. It gives about 20 hours of bonus time to continuous(mp3) use, or 4 ish charge cycles.
Title: External Battery Pack With Sl-5500?
Post by: t0xa on May 12, 2006, 06:29:04 pm
Quote
I built a brick that uses 4AA batteries through the charging port. It gives about 20 hours of bonus time to continuous(mp3) use, or 4 ish charge cycles.
[div align=\"right\"][a href=\"index.php?act=findpost&pid=126806\"][{POST_SNAPBACK}][/a][/div]

Can you post some photos of this monster?