There was a recent post about using the magneto to charge the battery, if so equipped. Knowing that the early Ts were retro fitted with electric lights, some enterprising owner or shop must have thought of the same concept - charging the auxiliary battery from the alternator. Of course they may have learned one way or another the battery needs DC voltage to charge a wet cell. So how to charge a battery from AC voltage.
In 1923 Western Electric had a patent filed on their behalf for an ELECTROLYTIC RECTIFIER. A means to convert AC to DC. The question, has any one seen or found a T with such a device in car to charge a battery? (http://www.google.co.uk/patents/US1607075)
One other note, such a device appeared in the Ford Car Trade Journal, 1920, listed as the Fordrektafier. Also a mention of a similar device in Horseless Age (?) 1917.
Where is the rest of the drawing. There is no rectifier to convert AC to DC?
It is all there. The wonders of the 1920's! If you read the patent there is an explanation.
From a questionable wiki:
Electrolytic """The electrolytic rectifier was a device from the early twentieth century that is no longer used. A home-made version is illustrated in the 1913 book The Boy Mechanic but it would only be suitable for use at very low voltages because of the low breakdown voltage and the risk of electric shock. A more complex device of this kind was patented by G. W. Carpenter in 1928 (US Patent 1671970).
When two different metals are suspended in an electrolyte solution, direct current flowing one way through the solution sees less resistance than in the other direction. Electrolytic rectifiers most commonly used an aluminum anode and a lead or steel cathode, suspended in a solution of tri-ammonium ortho-phosphate
The rectification action is due to a thin coating of aluminum hydroxide on the aluminum electrode, formed by first applying a strong current to the cell to build up the coating. The rectification process is temperature-sensitive, and for best efficiency should not operate above 86 °F (30 °C). There is also a breakdown voltage where the coating is penetrated and the cell is short-circuited. Electrochemical methods are often more fragile than mechanical methods, and can be sensitive to usage variations, which can drastically change or completely disrupt the rectification processes.
Similar electrolytic devices were used as lightning arresters around the same era by suspending many aluminium cones in a tank of tri-ammonium ortho-phosphate solution. Unlike the rectifier above, only aluminium electrodes were used, and used on A.C., there was no polarization and thus no rectifier action, but the chemistry was similar.
The modern electrolytic capacitor, an essential component of most rectifier circuit configurations was also developed from the electrolytic rectifier.""""""
This offering was made to recharge the batter from the mag.
Oh, So that's a rectifier instead of a battery. Now I See. The battery connects to the two wires. Sure, anyhing that only allows current to flow in one direction is a rectifier. Today a simple diode with a light bulb in series to reduce the current does the trick and works very well. .
The question is this: Has any one found, seen, or have a car that has or had a Fordrektafier or a home made unit on a car? Yes the diode and light of the late 20th/21st century is simpler.