Early Electric Car Charging

By Scott Wilson

What follows is what I’ve learned on the subject of how exactly the first generation of EVs were charged. This is interesting, since there are many striking parallels between how charging was done then and how it’s done now.

If I had a Detroit Electric or Baker, or any of several electric cars in the early 20th century, how would I charge it? One possibility would be that the dealer would keep it charged for me at their own charging location, and I would request it when needed.

(ruralroads.org)

(Power Wagon, 1906)

Cars would either be charged with the batteries on board, or the batteries would be removed and charged centrally in the “battery room.” Batteries were also swapped in electric trucks and taxi’s.

This is the Garage at Cooke and Stoddard, at 1138 Connecticut Ave NW in Washington DC, which sold Baker electric.

Notice the three bulbous, glowing mercury arc rectifiers, whose purpose is to convert AC power to DC power. We’ll explain how they work later.

Here is the charging cable, pulled down from overhead, going into the car.

Chargers designed for a garage.

But, what if I wanted to buy my own charging outfit? The charging equipment I used would depend on whether I had DC service or AC service at my residence, since both were available. Both the DC and AC chargers looked similar. This is an AC charger:

You can spot right away it’s an AC charger since it has the same mercury arc rectifier shown above, labeled “rectifier tube” on the drawing.

Another view:

The DC chargers are similar in appearance:

Here’s a more useful view of how these devices worked. More details below.

In my garage or parking spot, I would set up my charging outfit,

the same as we do today.

Here’s a close-up of the charger,

with the connector.

There have been many connector standards over the years. What did plugs look like back then?

This shows the two dimensional size standards, the smaller rated at 50 amps, the larger at 150 amps.

The upper male connector was on the cable, the bottom female socket was on the car.

Compare, for example, with SAE J1772.

Here’s another example of a charging outfit. This was GE treasurer Samuel Whitestone’s garage at 7 Douglas Road in Schenectady, NY, 1911.

You can tell it’s AC by the rectifier shaker switch in the center of the slate panel.

Support hardware for the main charger.

Another example from Newark, NJ, around 1910, with the charger highlighted.

Then again, there was Andrew Carnegie’s garage, complete with uniformed staff.

This the spec sheet for GE automobile chargers,

and chargers for smaller ignition batteries.

You could order custom chargers. Here is the form for ordering a charger from GE:

Here are some more GE examples. Notice the modularity.

This is a close-up showing the rectifier tube and circuit. Note lots of exposed electrodes and wiring.

A brief aside on how mercury arc rectifiers work:

First of all, here’s what it looks like in action:

http://www.youtube.com/watch?v=yjMZ5qtyCUc

Here is a detailed examination of a charger owned by the Edison Tech Center, Schenectady, NY:

Here’s how the tube works, courtesy of General Electric. It’s actually pretty clear.

In order to start the arc, you would tip the tube, which was mounted in a rocking mechanism, to the side, causing the mercury to short to the ‘starting electrode’ at C, then when you brought it back to vertical, the arc would be maintained as described.

You may ask how AC electricity is converted into DC nowadays? After humanity discovered the amazing properties of nearly pure silicon with tiny amounts of added group III and group V impurities, we invented silicon diodes, which are one-way “valves” for current. The equivalent operation today is performed by a circuit called a bridge rectifier, made out of an arrangement of four diodes:

There was also the “Electrant” or electric hydrant, made by General Electric, which has a creepily familiar look to today’s EVSEs. It was meant to be public charging as common as police call boxes and horse hitching posts. It would deliver 2.5 kWh of energy for 25 cents, which, at 10 cents per kWh, is also oddly similar to todays electric rates. (Edwin Black)

Here are some of the modern embodiments of the same idea.

Here are examples of surviving chargers. First, the America On Wheels Auto Museum, Allentown, PA.

The Edison Tech Center, Schenectady, NY.

Collector Randy Ema has a General Electric No. 79811, 30 amp Type MS charger.

Here’s a nice view of the mercury rectifier.

From the Detroit Historical Museum:

And, in the UK,

This unit has it’s rectifier front-mounted, which was used for charging small ignition batteries for gasoline cars.

Here’s a beautifully restored charger.

And another:

From the LeMay – America’s Car Museum, Tacoma Washington:

Then, as now, you arrive home and plug it in, just like we’re rediscovering today.

Bibliography:

“Planning Rural Roads/electric Traction.” N.p., n.d. Web. 3 May 2013.

“Stabling Electrics.” The Power Wagon 24 May 1911: 3. Print.

“Features of an Electric Stable.” The Power Wagon 31 May 1906: 9. Print.

“1912 GE’s Electric Charging Station.” N.p., n.d. Web. 3 May 2013.

Schreiber, Ronnie. “Plus ça Charge: Electric Touring.” The Truth About Cars. N.p., 16 Feb. 2013. Web. 3 May 2013.

Harris, Gideon. Audels Answers On Automobiles. London, New York: Theo. Audel &, 1912. Print.

General, Electric. Bulletin Issue 4472, General Electric Company. Schenectady, NY: General Electric, 1906. Print.

Van Den Bossche, Peter. “The Electric Vehicle: Raising the Standards.” Diss. Vrije Universiteit Brussel, 2003. Print.

Gartner, John. “The Slow Process of Ev Charging Standardization.” plugincars. N.p., n.d. Web. 3 May 2013.

Comstock, Wm. Phillips. Garages and Motor Boat Houses. New York: William T. Comstock Company, 1911. Print.

berms03. “Full Bridge Rectifier.” All About Circuits. N.p., 24 Sep. 2012. Web. 3 May 2013.

“Public Electric-vehicle-charging Station.” Electrical World 16 Jan 1915: 179. Print.

“Robletcherpa’s Photostream.” N.p., n.d. Web. 3 May 2013.

“Mercury Arc Rectifiers.” Edison Tech Center, 2013. Web. 3 May 2013.

“Randy Ema’s Charger.” Milburn Light Electrics. Myles Twete, n.d. Web. 3 May 2013.

Schreiber, Ronnie. “Plus ça Charge, Plus C’est La Même Chose.” The Truth About Cars. N.p., 2 May 2012. Web. 3 May 2013. <>.

“Gallery: Gems from GE’s Archives.” PopSci. PopSci, 8 June 2011: Web. 3 May 2013.

Purcell, Russell “Lemay – America’s Automotive Museum.” N.p., 16 Aug. 2012. Web. 3 May 2013. <>.

Black, Edwin. Internal Combustion. New York: St. Martin’s, 2006. Page 68. Print.

Magda, Mike. “New Book Has 1912 Photo of Electric-Car Charging.” autobloggreen. N.p., 18 Nov. 2006. Web. 3 May 2013.

Fountain, Henry. “How to Charge Millions of Electric Cars? Not All at Once.” New York Times. N.p., 24 Apr. 2013. Web. 3 May 2013.