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bids to acquire Sanyo Electric financial firm Goldman dell laptop batterySachs has finally accepted an offer from Panasonic to acquire Goldman’s stake in the company. Goldman will now join Sanyo’s other major shareholders, Daiwa Securities SMBC and Sumitomo Mitsui Banking, in relinquishing control of Sanyo and allowing Panasonic to create an electronics giant.

Panasonic announced their intentions to acquire Sanyo last month but had to revise offers made to Goldman in order to complete the deal. Daiwa and Sumitomodell Inspiron 600m battery initially accepted the offer from Panasonic and are expected to go along with the final deal to be made official by both Panasonic and Sanyo on December 26th.

Goldman finally accepted an offer from Panasonic estimated to be 131 yen per share ($1.47) although that figure is still considered to be below Sanyo’s market price. The final offer price for the acquisition is expected to be near 560 billion yendell Latitude D500 battery, or $6.36 billion with a tender offer as early as February 2009. Panasonic is interested in acquiring anywhere from 50% to all of Sanyo’s shares.

The merger will create a consumer electronics giant that will be able to compete globally with other leading electronics and battery companies in China and South Korea. Panasonic, which manufactures everything from televisions to Blu-ray dell Latitude D505 batterydisc players, is interested in capitalizing on Sanyo’s industry leading “green” technology including solar panels and rechargeable batteries. The technology and patents owned by Sanyo will allow Panasonic to expand their reach into fields previosuly dominated by Sanyo and perhaps signal a shift in car manufacturing to include dell Latitude D510 batterylithium-ion batteries and other renewable energy sources.

The Li-Ion battery in my dell laptop battery laptop has been getting a bit long in the tooth. Rated at a 4.4 AH capacity new, /proc/acpi/battery/BAT0/info told me that it was only holding 1.8 AH now that it was a few years old. (This is normal for Li-Ion batteries, which degrade over time, even without multiple charge-discharge cycles.)
A brand new IBM (or Lenovo now) battery costs over a hundred dollars, but by shopping around I was able to find a "compatible" battery for as low as $50. It was only rated at 4.4AH, but that is relatively close to the 2nd generation 4.8AH batteries that IBM/Lenovo sell for twice as much. I started to wonder dell Inspiron 6000 battery if it might be cheaper to buy OEM li-ion cells and simply replace the cells (keeping the case, and charge/discharge electronics). The first step would be to determine what type of Li-Ion cells I'd need to buy, so I decided to open up my old battery.
As you can see, the standard X31 battery has six cells, in three parallel groups of 2. Cells are nominally 3.6volts, so this adds up to 3 x 3.6 or 10.8 volts. In the photo I have removed the shrink wrapped packaging from one cell to view the markings. Note the relatively complicated PCB along the back side of the cells that handles charging and discharging. If you zoom into the photo, you can see that the controller PCB is connected to each end of every pair of cells (orange and black wires to the far ends, silver metal tab connections to the middle two). This allows the controller to dell Inspiron 9300 battery charge each parallel pair of cells at a different rate. The controller PCB is also connected to a thermocouple that is resting between the two middle cells. This gives the controller a temperature reading on the cells during charging and discharging. If the PCB detects that the temperature is too high, it can lower the charging rate, or shut down the power draw (and laptop). Also note the heat fuse (small white block in series with the power line between the two leftmost cells) that is designed to open the circuit if the charge/discharge controller for some reason fails to maintain a safe temperature. All of these dell Inspiron 9400 battery safeguards are designed to keep your laptop battery from igniting, and will be very important to maintain in any "re-manufactured" batteries.
I actually determined what type of li-ion cells were used by measuring them and then looking for li-ion cells of a similar size. They are about 2.5" high by 11/16" diameter, or very close to the 64.9mm x 18.3m diameter size of a 18650 style cell that I found on www.batteryspace.com.
My battery is rated at 4.4AH, or 4400mAH. As it has three sets of parallel cells, each set of two cells must have a 4400mAH capacity (because they are in series, you add the voltage, not the amperage), so each cell must have a 2200mAH capacity.
From a mAH per dollar standpoint, dell 310-6321 battery batteryspace.com's 2000mAH cells are the best value, but I decided that since the total cost difference was only six dollars, I could afford purchasing the 2200mAH cells. These are slightly lower than the 2400 mAH capacity of the newcells that Ibm/Lenovo now use, and I'll end up with a 4.4AH battery (just like the original part number, before IBM/Lenovo upgraded it to 4.8AH).
Just the cells cost $34.20, but I chose to purchase them with solder tabs attached (an extra $1.50) because I figure the people at batteryspace.com are better than me at attaching tabs, plus having extra tabs to work with (those that come on the cells, plus those I salvage from the original cells) will make my life easier. (Besides, the $7 of shipping is the largest extra expense….if the 2600mAH cells weren't almost twice as expensive as the 2200mAH cells I'd have gotten them just get a 5.2AH capacity battery!) The total cost was $43.42. A week later my batteries arrived.