I've got too much time, and decided to come out with this post Above is a power-bank that I got off Qoo10. It is advertised as featuring a Samsung SDI battery. I don't really believe what the seller state nowadays, especially power-banks, therefore decided to took apart the battery.
The disassembly revealed the cell that is used to power our electronic gadgets. Information as below...
2D52 means the cell is manufactured in 2013 at Week 52 (from my research) There are two LED indicators on the IC chip itself to display the charging and charged status
How the power-bank works is that the 3.7V voltage from the battery is stepped-up to 5V by the IC chip and then supplied via the USB port. But how safe is the power-bank itself against short-circuit? I've tested the power-bank by purposely short circuiting mine. The power-bank disabled itself from further charging. Just when I thought that the power-bank is spoilt, I took it to charge and volia, it worked again! I'm thinking the charging procedure basically grounded the shorted circuit in the power-bank and made it work again. One point to note is that one of the poles of the battery is soldered onto the wire itself. According to Samsung specification, manufacturer aren't suppose to solder the wires directly onto the poles on the battery. Considering that the power-bank is just SGD$4.90, I'll let it go. I've also tested the power-bank using a multimeter to ensure that it was outputting 5V. The results is that the output voltage fluctuates quite a bit. Minimum from 4.9V to about 5.1V MAX. So it definitely outputs the right voltage. I wasn't able to test the Amperage as a load is needed when measuring. I did a full charge of the power-bank and used it to charge my iPhone 5 from a completely dead state to full. In fact, I was quite surprised that it is able to charge it once. I've had another power-bank before that is also rated at 2600mAh, but only able to charge my iPhone 5 to 80%. That is also the reason why I am so skeptical about the capacity of those power-banks sold out there online. The enclosure of the cell is pretty weak/fragile, so you might want to keep it away from liquid, etc. I mean water can very easily seep into the power-bank internals causing all around short circuit or even explosion... In overall, the power-bank was a pretty good deal at just SGD$4.90 + SGD$1.00 for shipping That's it :D DISCLAIMER: I'm just doing this for fun and NOT to help the seller boost sales in any way PS. I don't even know the seller at all...... As always, take care and I'll see you soon :) Signing off @ 3:23am I'm working on another new version of Medduler QR Data Manager before releasing the full source and application online. The new version aims to dramatically improve on a few things that are vital to how the application works...
I'm in the stage of trying out the new procedure with a few dummy files to see the performance and stability of the new implementation. Until now, what I have to say is that it works, but I fear it might hinder other parts of the application. Therefore, thorough testing and checks must be done before the new version is officially released. It will also completely remove the errors caused by clash in file names! Even though it should not happen, but completely eliminating it is definitely good :) As always, take care and I'll see you soon :D Signing off @ 1:45am Hi everyone...
I've just updated the FYP page to Medduler and updated the screenshots of my Windows application. The Android application also recently received another update to enable support for even more devices. Before that, we only tested our application on Nexus devices by directly installing the APK file. The application worked well on Nexus devices, but Google Play doesn't let Nexus 7 install the application due to a lack of 'rear' camera support on the device. But now it is working for the Nexus 7 in the new update (Recognized by Google as supported, it was already supported) Nexus 7 is just an example, there are actually a bunch of devices that are enabled with this update Have an appointment at NUH on Monday for my throat. I really hope it is nothing serious, but considering that it has been so long, I wouldn't be surprised if it was anything bad :( I'm also considering getting my wisdom tooth removed, as it might be causing the blood in mouth issue. I should have a better idea whether the blood is coming from my throat or mouth on Monday after the check. I also watched a few videos on YouTube regarding the surgery and it was extremely bloody. Basically the procedure in removing the tooth requires the slicing of the gums, then slight drilling to remove the bones holding the wisdom tooth, then the actual removal of the tooth. The sliced gums is then stitched back using thread and left to heal on its own. It might sound easy, but then I really have no idea how much pain is involved when my gums are 'sliced' open, and bones drilled :( As always, take care and I'll see you soon... |
Updated: 20 Aug 2021
Steven Ching
Dazhong Primary School Bukit View Secondary School Singapore Polytechnic (Diploma in Computer Engineering) University of Wollongong (Bachelor of Computer Science - Digital System Security with Distinction) Infantry Specialist (3SG NS) Archives
August 2021
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