Monday, June 2, 2008

Fact about maintenance-free battery of car

Nowadays, most car battery is a lead-acid storage electrochemical device that can converts chemical energy into electrical energy. A standard 12-volt, lead-acid battery is made up of 6 cells connected in series. Each electrolyte filled cell produces approximately 2 volts. The charge of this 12-volt battery is actually at 12.6 volts, and can vary slightly depending on the concentration of the electrolyte in its acidic solution.

The "maintenance-free" battery, similar in design to its conventional counterparts that need to refill with distilled water from time to time to maintain the fluid level, is actually just a heavier-duty version of the same arrangement. Many of the components in the maintenance-free battery have thicker construction. Different, more durable materials are typically used. For example, the plate grids often contain calcium, cadmium or strontium, to reduce gassing (which causes water loss) and self-discharge. This design is called a lead-calcium battery. The heavier-duty parts ensure that fluid loss is kept to a minimum and that components have a much longer life, making it a closed system.

The advantages of maintenance-free battery are: less preventative maintenance, theoretically longer life, faster recharging, greater overcharge resistance, reduced terminal corrosion and longer shelf life. However, they are more prone to deep discharge (dead battery) failures due to increased shedding of active plate material.

Grounding cables for car

Everything involving the electrical systems in your car requires a free flow of electrons from -ve to +ve terminal of the battery (note that the conventional current flow from +ve to -ve used in most circuit diagram is opposite to the actual electron flow).

Good electrical performance requires a grounding system that is capable to carry a lot of current with minimal resistance. Your car's engine control unit (ECU), spark plugs, lights, in-car entertainment (ICE) components, air conditioner, fans, power windows, cigarette lighter, etc. are all working on a complicated electrical network that includes fuses, relays, and electrical cabling, and they all share a common ground. Almost everything that is powered electrically in your car is grounded to the frame or the metallic body of the car. The negative battery terminal is also grounded to the frame, which causes the frame to serve as a gigantic piece of wire in the circuit.

Usually, the stock grounding system of the car consists of just a few non-braided cables that connect the chassis, engine and firewall to the -ve terminal of the battery. The cables are of normal quality only. In addition, as these connections oxidize or come loose over time, the amount of conductive material decreases, and the electrical devices have to work much harder to overcome the increased resistance.

By installing additional grounding cables connecting the various grounding point or point closest to the various components of the electrical system, and link it directly back to the -ve terminal of the battery, the result is: an alternative path is provided for better flow of the electrical current, via the lower resistance paths. The grounded electrical components are expected to work more effectively with better performance.

The current flow will always take the path of least resistance. Therefore, adding grounding cables to your car can only make the different if the additional cables are of higher quality and lower resistance than the stock grounding system.

Characteristic of grounding cable is determined by American Wire Gauge (AWG) specification. The larger the AWG number, the smaller diameter of the wire. For example, 4-AWG cables are better than 8-AWG cables, because they have thicker diameter, lower resistance and higher current carrying capacity.

Grounding cables are good companion to voltage stabilizer, and usually they are installed together to obtain the best performance.

Sunday, June 1, 2008

Added flag counter starting from 1 June 2008 noon

I notice this flag counter in the blog of Taryn Yap today, and decided to add one for my blog too. So you can see it also resides in the right panel of this blog from now onwards.

This flag counter is a free service provided by Boardhost.com Inc. and is very easy to deploy. It is so easy that you don't even need to create any account to have one in your website.

The counter is counting on unique visitors, and makes use of IP address as well as browser cookie to avoid repeated counting from the same visitor. Every time a visitor from a new country visits your page, a new flag will be added to your counter. Detailed information from the Factbook of CIA about each of the country can be shown after you click on the flag counter to show more detail.

Click here to get your own flag counter from flagcounter.com.

Hint: Click on the "Older Posts" link to continue reading, or click here for a listing of all my past 3 months articles.