Battery Tests, Homemade 3000mAh XL Battery & Q&A (POST #1) - New Layout - Page 21 - maemo.org

dr_frost_dk | # 201 | 2011-02-07, 01:11 | Report

Originally Posted by WildWere View Post

What's the physical size of the 2 A fuse (width hight length) ? Maybe I can help, and maybe a picture so I can see the design of the solder contacts.

I wasn't "stupid" comparing. As you and I already know the energy in a battery is a electrochemical reaction and you do get a better preforming battery after a long first charge in the Nickel-cadmium battery (NiCd) I just wanted to know if this could be achieved with a Lithium Ion battery. I now know that the instructing to charge the battery for 8 hours or more for the first time is a leftover from the nickel battery days.
Also the Li-Ion batteries age over time, regardless of whether they are used or not. A typical Li-Ion battery will last for a year and will typically need to be replaced in two years. I found information that a number of places on the Internet sell surplus Li-Ion battery packs. Many of these cells may have already past the two-year point at which their internal resistance prevents them from providing much of their energy,

I have done some reading

Maybe the charge current of Li-ion should be moderate (0.5C)
The lower charge current reduces the time in which the cell resides at 4.20V. I read that a 0.5C charge only adds marginally to the charge time over 1C because the topping charge will be shorter. A high current charge tends to push the voltage up and forces it into the voltage limit prematurely.

not saying your stupid, just the battery type.... been there, damm memory effects and such, battery life does not seem to be affected too much with charging close to 1C, i charge my dual japod with 0.9C (2.5A), and my electro ciao (Vespa Ciao converted to Electric) has 11 mounts on the battery now with no problems, but can feel the capacity drop from close to 300 charge cycles so far.... but not going to go cheap next battery upgrade it's going to be LiFe not LiPo

on the fuse subject... it is really really really small. i have soldered some SMD in my time but this is one tiny little thing
Schematic
in the schematic go to page 17 and in the grid (H 4) find the fuse labeled F5300

WildWere | # 202 | 2011-02-07, 03:01 | Report

Originally Posted by

my electro ciao (Vespa Ciao converted to Electric) has 11 mounts on the battery now with no problems, but can feel the capacity drop from close to 300 charge cycles so far.... but not going to go cheap next battery upgrade it's going to be LiFe not LiPo

I am more of a petrol head my self. I would just go for a bigger carburettor higher compression better flow and a tuned pipe. For a little 2 stroke tuning i recommend this page Topplocksverkstan
I found this interesting reading Iron_phosphate_battery
But as you said earlier, lets keep this tread clean

Originally Posted by

on the fuse subject... it is really really really small. i have soldered some SMD in my time but this is one tiny little thing
Schematic
in the schematic go to page 17 and in the grid (H 4) find the fuse labeled F5300

You are right. It IS really really really really tiny. You need a hot air soldering gun and I think after loosely studied the schematic it's not worth the effort. These fuses often are there fore extra security if something else goes wrong, like some enthusiast trying to recharge a dubble Japod mod being tired reversing the polarities

. (Done that with motorcycles computers other electronics and some sensitive electric stuff, otherwise we never learn. Just can't keep my fingers away) Nah ! If one is to worry about the N1140 USB charging IC or the I/O IC just put a fuse on the Usb cable or maybe if its accessible solder pin 1 on the usb connector through a 2 A fuse of your choosing. I dropped a battery powered drill on my n900 cracking the touch screen and display. Bought a new n900 for 525$. I ended up repairing it selling it to my brother but I should just have bought the the new one using the old one for spare parts.
BUT I don't think it is impossible either using a fine hot air soldering gun and a small tweezer, with some risk damage the surrounding components. If you have insurance send it in they will probably change the phone out.

indeo | # 203 | 2011-02-07, 03:18 | Report

Just ordered a Japod battery for my N900. Thanks for the research

dr_frost_dk | # 204 | 2011-02-07, 09:27 | Report

Originally Posted by WildWere View Post

I am more of a petrol head my self. I would just go for a bigger carburettor higher compression better flow and a tuned pipe. For a little 2 stroke tuning i recommend this page Topplocksverkstan
I found this interesting reading Iron_phosphate_battery
But as you said earlier, lets keep this tread clean

You are right. It IS really really really really tiny. You need a hot air soldering gun and I think after loosely studied the schematic it's not worth the effort. These fuses often are there fore extra security if something else goes wrong, like some enthusiast trying to recharge a dubble Japod mod being tired reversing the polarities

. (Done that with motorcycles computers other electronics and some sensitive electric stuff, otherwise we never learn. Just can't keep my fingers away) Nah ! If one is to worry about the N1140 USB charging IC or the I/O IC just put a fuse on the Usb cable or maybe if its accessible solder pin 1 on the usb connector through a 2 A fuse of your choosing. I dropped a battery powered drill on my n900 cracking the touch screen and display. Bought a new n900 for 525$. I ended up repairing it selling it to my brother but I should just have bought the the new one using the old one for spare parts.
BUT I don't think it is impossible either using a fine hot air soldering gun and a small tweezer, with some risk damage the surrounding components. If you have insurance send it in they will probably change the phone out.

just the last comment on the battery, lithium iron phosphate (LiFePO4) is the ones im going to be using in the future, and have had about 150 2strokes mopeds in my time so far (buy, fix up, ride and resell

) and have tuned plenty, but i am not going back to fuel since i started my EV thing, it is so much more nice in every way, just like the way im not going back to MS since i began with linux a year ago. - more discussion lets keep it to PM

And i have modded so much my phone to even think that i can get nokia to replace/fix the fuse, i had to cut some of the screen off to get to the fuse, when i take the phone apart again to change the touchscreen (scratches....) i will take a picture and post it on this thread.
But if i had a fuse that fit i would be able to fix it myself, not that i wouldn't want anybody else to do it, anybody with better equipment then i have when dealing with SMD.

bat_malin | # 205 | 2011-02-07, 09:33 | Report

Just one question. Why there isn't a LiPO(Lithium polymer) battery for N900. I have also N82 which is powered by a LiPO batt. with 1050Mah capacity and have almost the half of the size of the original N900 batt.?

shadowjk | # 206 | 2011-02-08, 01:38 | Report

Technically the N900 battery is Lithium Polymer. Without polymer technology the battery would need to be kept together under pressure by a metal container. The material under the outer plastic shell is more like a soft bag than hard metal box.

Laptops on the other hand often use non-Polymer batteries in the form of cylindrical cells connected together.

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dr_frost_dk | # 207 | 2011-02-08, 01:50 | Report

Originally Posted by shadowjk View Post

Technically the N900 battery is Lithium Polymer. Without polymer technology the battery would need to be kept together under pressure by a metal container. The material under the outer plastic shell is more like a soft bag than hard metal box.

Laptops on the other hand often use non-Polymer batteries in the form of cylindrical cells connected together.

Yes most common is the 18650 Cells, and boy do i have some of those lying around... new ones, old ones from laptops, funny side note when talking about laptops, many of the battery's i have taken apart have been good still, only thing wrong with the battery is the electronic controlling the battery e.g. preventing over charge/discharge and balancing the cells

shadowjk | # 208 | 2011-02-08, 06:01 | Report

I think some of them have electronics that can't balance, so it stops working once a cell goes out of balance with the rest...

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WildWere | # 209 | 2011-02-08, 13:43 | Report

Originally Posted by

i had to cut some of the screen off to get to the fuse, when i take the phone apart again to change the touchscreen (scratches....) i will take a picture and post it on this thread.

What ? Why ? I have disassembled my phone several times without having to cut in the screen. Yes a Picture would be very interesting.

Originally Posted by

But if i had a fuse that fit i would be able to fix it myself, not that i wouldn't want anybody else to do it, anybody with better equipment then i have when dealing with SMD.

I don't have good surface mount equipment anymore but surface mounted fuses should not be a problem to find.
Could it be something like this ? It's a bit hard to see size in the schematics.

dr_frost_dk | # 210 | 2011-02-08, 15:29 | Report

Originally Posted by WildWere View Post

Could it be something like this ? It's a bit hard to see size in the schematics.

nope thats about 3 times longer than the fuse in the phone.
it is next to impossible to remove the fuse without removing some of the screen base, i had to do it to get to the damm thing.