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KA5PIU
11-20-2010, 07:40 AM
Hello.

I like to play with batteries and flashlights and radios, and pretty much everything else. :lol:
My ibook battery took a nosedive so I pulled it apart, 18650A cells, oh goody!
This is a 3 cell series and 2 parallel configuration, 6 cells total.
I found some poly cells that almost the exact size of the inside of the pack but greater capacity.
So I wired that up and tested it, works great.
Of course I use protected cells and am now using RC power connectors inside, everything for safety.
After one weeks use I can now say it is a success!
The total cost of the rebuild was under $50, and I have over twice the runtime.

n2ize
11-20-2010, 07:48 AM
What type of cells are you using ? If you are using LiPo cells (such as those used for RC stuff) be careful. They are very volatile and if they are not charged properly the results are not pretty. In any event to charge LiPo's you need a cell balancing charger. Don't use a standard NiMH, Nicad, or Lithium-ion charger.

KA5PIU
11-20-2010, 07:55 AM
What type of cells are you using ? If you are using LiPo cells (such as those used for RC stuff) be careful. They are very volatile and if they are not charged properly the results are not pretty. In any event to charge LiPo's you need a cell balancing charger. Don't use a standard NiMH, Nicad, or Lithium-ion charger.

Hello.

Yes, LiPo, the laptop charges the cells as a set of 3 cells and the protection circuit takes care of discharge.
http://www.candlepowerforums.com/vb/showthread.php?t=204823

N2CHX
11-20-2010, 11:15 AM
Pretty soon there will be a Youtube video of Rudy putting out his iBook with a sleeping bag and kool aid.

KA5PIU
11-20-2010, 11:57 AM
Pretty soon there will be a Youtube video of Rudy putting out his iBook with a sleeping bag and kool aid.

Hello.

I am using protected cells as well as the original ibook control circuit, and have added pico fuses and connectors.
The thermistor and sense resistors are still in place.
I was debating building the circuit to intrinsic safe standards, I have the boards out of some bad Motorola batteries, but felt this to be overkill.
As it stands now, any sort of abnormal operation will cause a shutdown, and there are 2 complete safety circuits per cell as well as the thermal and current fuses.

n2ize
11-20-2010, 02:30 PM
Was the original ibook control/charge circuit designed for LiPo's. If not, be careful !! Even with proper circuit and thermal protection you need to use a charger that is designed for LiPo batteries. Particularly critical is to make sure the cells are charged at or below the maximum rate for the particular cell. The charger also needs to have a balancing circuit, to make sure that each cell's voltage remains within close tolerances of each other. Also, be careful discharging them. Lipo's are easily damaged if they are discharged at a rate above their recommended capacity and, they are also damaged if they are overly discharged. At no time should a LiPo battery be discharged to below 3V per cell. Many commercial LiPo chargers won't even charge a pack if the cell voltage is below 2.5 - 3.0 volts. Be very careful that they are not overcharged. Overcharging (or charging at too high a rate) will usually cause the cells to puff, overheat and, burst into flames quite dramatically. Lipo's also easily burst into flames if they are shorted (even for brief periods) or if their cases (which are usually soft foil cases) are punctured.

In the Rc hobby we have a general rule for LiPo's. We never charge them unattended... House fires have been known to occur when persons put the batteries on charge and walk away.

It is also a good idea to check them for puffing. If you see the cases are bulging and puffed that is generally not a good sign.

Last but not least, here is an example of what a LiPo fire looks like. Not something you'd want to have happen indoors.


http://www.youtube.com/watch?v=VswaFOrVM6I

kb2crk
11-20-2010, 04:05 PM
Hello.

I like to play with batteries and flashlights and radios, and pretty much everything else. :lol:
My ibook battery took a nosedive so I pulled it apart, 18650A cells, oh goody!
This is a 3 cell series and 2 parallel configuration, 6 cells total.
I found some poly cells that almost the exact size of the inside of the pack but greater capacity.
So I wired that up and tested it, works great.
Of course I use protected cells and am now using RC power connectors inside, everything for safety.
After one weeks use I can now say it is a success!
The total cost of the rebuild was under $50, and I have over twice the runtime.

i have bought more than a few brand new laptop batteries for under 50 bucks. i can usually get two for under 50 and no time lost putting them together.

KA5PIU
11-20-2010, 04:10 PM
Hello.

No, the original charge circuit of the iBook was not designed for this type of cell, that is why I use protected cells and a safety/charge circuit.
The safety circuit I use limits the charge current to 800ma.
Each cell is monitored an.d charged as one cell, the original iBook design.
But above all, I designed this to exceed ICAO standards for a computer in the cockpit of an aircraft, any aircraft.
In order for a battery to explode or catch fire it must heat to a given point, usually well above the boiling point of water.
Fuses will open long before that time.
Or excess current, again, fuses everywhere.
But the thermistors are set for anything over 150 degree.
Again, I had debated to build this to intrinsic safety standards but decided not to.
From full dead to full charge is 11 hours as each cell must match the other 2 and so the slowest charging cell sets the pace.
I also have another battery pack that I can play with, perhaps IS is the way to go with this one, who knows?

kb2crk
11-20-2010, 04:21 PM
now there is a scary thought. rudy typing on a laptop as he is flying the helicopter.....lol

KA5PIU
11-20-2010, 04:47 PM
i have bought more than a few brand new laptop batteries for under 50 bucks. i can usually get two for under 50 and no time lost putting them together.

Hello.

I have found that the iBook batteries are harder to find.
If you have any pointers I would love to hear them. :yes:

kb2crk
11-20-2010, 04:57 PM
Hello.

I have found that the iBook batteries are harder to find.
If you have any pointers I would love to hear them. :yes:

http://shop.ebay.com/?_from=R40&_trksid=p5197.m570.l1313&_nkw=i+book+battery&_sacat=See-All-Categories

took less than 30 seconds.

W3MIV
11-20-2010, 08:26 PM
My ibook battery took a nosedive so I pulled it apart, 18650A cells, oh goody!
This is a 3 cell series and 2 parallel configuration, 6 cells total.

Mercy! That's some bunch of amperage, Rudi. You could build your own substation.

KA5PIU
11-20-2010, 08:38 PM
http://shop.ebay.com/?_from=R40&_trksid=p5197.m570.l1313&_nkw=i+book+battery&_sacat=See-All-Categories

took less than 30 seconds.

Hello.

Used batteries or new old stock is cheap but iBook batteries have a limited shelf life.
The cells I have in the rebuild are 8250 milliamp-hour.
The original pack was 2200 ma-hr.
Due to the design of the charge circuit the battery pack will never hit a true 100% charge, 96% is it.
This is still over 4 times the run time in theory, in practice it is actually 8 times.

kb2crk
11-20-2010, 08:47 PM
these are new battery's with double the amp hours of the original for less than 35 buck apiece and have a warranty . they also have no risk of burning up like IZE's picture.

KA5PIU
11-20-2010, 10:34 PM
these are new battery's with double the amp hours of the original for less than 35 buck apiece and have a warranty . they also have no risk of burning up like IZE's picture.

Hello.

Actually, ;) some of the iBook batteries have indeed burst into flames.

http://chris.pirillo.com/laptop-fire/

http://www.tuaw.com/2006/06/01/ibook-battery-catches-fire/
Apple did a full redesign of the battery.
This has been so much of a problem that the ICAO has standards for computer power sources.
I was very careful to read the limitations on what can be done and have exceeded the requirements.
The iBook is normally a 1,3 GHz machine but while on battery power it is in "Hospital mode" and can only run 800 MHz.
Indeed, apple produced a "Hospital Grade" AC adaptor for this laptop to go with a Hospital Grade battery.
http://www.interpower.com/ic/medical_info.asp
http://en.wikipedia.org/wiki/Intrinsic_safety
This laptop was never offered in IS "Green Dot" configuration but I have the parts from Motorola battery packs that are Green Dot.
This safety circuit is a small board that has been produced to work with a lot of differing battery packs.
The reason being is that this board is tested and insured for the life of the battery and that is very expensive to do.
This is one of the very few products that Motorola produces that they will tell you everything about, and at no cost.
Ask around and you will get the IS battery manual from circle M.

NQ6U
11-21-2010, 12:06 AM
Rudy, I own AAPL stock and have followed Apple closely for the last twenty years. I've made my living as a a Mac support tech and reseller. I've even worked for them--indirectly, but closely enough that I had to sign an Apple NDA. I know something about the Macintosh computer and I feel comfortable saying this: Apple has never made a "hospital grade" AC adaptor for any of it's products.

KA5PIU
11-21-2010, 11:23 AM
Rudy, I own AAPL stock and have followed Apple closely for the last twenty years. I've made my living as a a Mac support tech and reseller. I've even worked for them--indirectly, but closely enough that I had to sign an Apple NDA. I know something about the Macintosh computer and I feel comfortable saying this: Apple has never made a "hospital grade" AC adaptor for any of it's products.

Hello.

This is what one looks like. ;)
3605
Notice the light green border around the power inlet and the (now well worn) green H with the square?
A normal Apple power adapter has one color for the power inlet.

NQ6U
11-21-2010, 11:30 AM
Rudy, I don't see either of those things you mentioned and, in fact, that power supply looks identical to the one that's powering the computer that I'm composing this message on.

KA5PIU
11-21-2010, 02:31 PM
Hello.

Yes but on yours the actual inlet is clearly one color.
Also look closely, the little silver button is almost the exact same size, yet the adapter I am holding is clearly fatter.
The higher power models are no fatter, just bigger and have a smaller diameter DC connector.
The primary difference between a regular power supply and the safety rated unit is that there are special capacitors inside that will not fit the regular housing.
http://www.johansondielectrics.com/technical-notes/application-notes/safety-certified-application-notes.html
You have the pictures, look for yourself, I feel that it is not that big a deal.
And to put it quite bluntly, I simply do not deal with VARs, I can get it cheaper and with better support from a big box than a mom and pop.
If walmart were to start selling Apple computers I would be there, guess where my iPad came from. ;)

NQ6U
11-21-2010, 02:54 PM
Rudy, to put it bluntly, I think you are making things up as you go along. The differences in size are due to that fact that mine is a newer model, designed for a MacBook Pro rather than your iBook. Not only that, I have to assume that you purposely posted that blurry picture so no one could tell whether what you are saying is true. If you look, you can see that my picture, which was taken with my computer's built-in Web cam, is sharp enough that you can read the part number. Any excuse for yours being so out of focus? Other than you were trying to hide the truth, I mean?

W7XF
11-21-2010, 02:54 PM
Once again, I call :bs:, Cowthief.

n2ize
11-21-2010, 03:05 PM
these are new battery's with double the amp hours of the original for less than 35 buck apiece and have a warranty . they also have no risk of burning up like IZE's picture.

Any high current density battery has the potential to explode and/or burn up, or cause materials near it to burn. LiPo batteries are particularly volatile but are still quite safe if charged, used and, when they reach then end of their useful life, disposed of properly. But LiON's, NiMh's and even Nicads can be pretty nasty.

kb2crk
11-21-2010, 04:25 PM
Once again, I call :bs:, Cowthief.


i call cow pie.....

KA5PIU
11-21-2010, 04:32 PM
Rudy, to put it bluntly, I think you are making things up as you go along. The differences in size are due to that fact that mine is a newer model, designed for a MacBook Pro rather than your iBook. Not only that, I have to assume that you purposely posted that blurry picture so no one could tell whether what you are saying is true. If you look, you can see that my picture, which was taken with my computer's built-in Web cam, is sharp enough that you can read the part number. Any excuse for yours being so out of focus? Other than you were trying to hide the truth, I mean?

Hello.

You are the expert in this field.
I posted a quick shot with a 640x480 webcam that has seen some very rough service.
When I want to post something from my cellphone cam I have to shrink it down so much that it looks even worse.
But who really cares? we went from rebuilding a battery and the pro and con thereof to exactly what type of power adapter is used on an iBook.
As was pointed out, batteries, even iBooks, can explode but precautions can be taken.
So far a protected cell with a class 2 UL and/or CSA rating has never exploded or caught fire, they simply quit working.
http://www.candlepowerforums.com/vb/showthread.php?t=280909
The charge circuit I have can not exceed 4.1 volts per cell nor over 800 mA and will not charge or allow discharge over 150 degree F.
This means that it simply can not be overcharged or over discharged and I will never get over 95% capacity.
But since this is almost 4 times the capacity of the original battery I am happy and that is all that matters.

KE7DKN
11-21-2010, 06:33 PM
It does not require many words to speak the truth.

KA5PIU
11-28-2010, 01:09 PM
Hello.

Confirmed it with the people at the Apple store in North Star mall.
A hospital grade iBook charger is designed to do 2 things.
First, it does not provide 24 volts DC or charge the battery, it provides 15 volts and has a resistor to tell the laptop to not charge a Lithium battery, a supported "safety" configuration.
You can do the same thing with this empower cable.
http://www.flyertalk.com/forum/archive/t-283323.html
But, hospitals are Required to do electrical safety checks of Everything that uses electrical power in the hospital.
http://www.iaei.org/magazine/?p=4561
Apple and GE medical products had a concern with this and can supply a power cube that can be megged to 5kv, no problem.
GE is the exclusive provider of Apple computers to the medical field, I read the contract, both retail and business parts of Apple sales as well as any VARs are prohibited from medical sales.
not saying you can not do it, but GE has the license as well as the people who do hipot testing on 100% of Apple products.
Hipot testing must be done on a regular basis.
http://www.cirris.com/testing/guidelines/hipot_testing.html

KA5PIU
12-02-2010, 11:47 AM
Hello.

CONFIRMED!
Hospital grade AC power adapters DO NOT CHARGE the battery on a laptop and Apple Computer has offered them for years.
Airline EmPower connectors are supposed to do the same thing.
http://en.wikipedia.org/wiki/EmPower_(aircraft_power_adapter)
Note that it is against federal law to use or charge an unapproved secondary battery device in an aircraft.
There is some limit on the size of the device that it must exceed in capacity and some other rules.
An iPod is exempt as it has a small battery that is charge limited internally and others may follow suit.

NQ6U
12-02-2010, 01:18 PM
Those are aircraft adapters, Rudy. Did you think no one would check your links?

KA5PIU
12-03-2010, 12:44 AM
Those are aircraft adapters, Rudy. Did you think no one would check your links?

Hello.

I made a second reference to EmPower, the aircraft thing.
But the specs for Apple iBook Hospital Grade AC adapters are close to that of the EmPower thing, and for good reason.
The HG stuff draws heavily on the research done by aviation, except for the HV and voltage leak testing.
My contact at Apple was Davian Bustillo at the Apple store located at 7400 San Pedro Ave.
San Antonio, Tx78216 (210)321-4420
Unlike some here, the Apple people have been most helpful, even with information on rebuilding batteries.
And, yes, I have 2 batteries that I have put against my rebuild.
The used battery has around 1300 mAh remaining.
A brand new aftermarket lists 4200 mAh.
My rebuild tests to 8900 mAh actual.
I will continue rebuilding batteries but will do a minor change.
Next rebuild I will drill a small hole in the pack and add an independent low rate charge circuit based on cellphone chips.
At a 10 hour charge rate and absolute voltage cutoff I can charge a pack to 80% from dead with no concern whatsoever.
The trick is in the rate of charge or discharge vs cell capacity.
10 hours is a long time in this instant gratification era.
But, the overall life of the pack is greater and the charge circuit is cheap.