battery chargers, again

John Larkin · 2009-09-28T04:16:46+00:00

Last time a car went dead in the garage, my wife's Fit, I hacked up acharger from an old DSL wall-wart and a sabre saw as a series currentlimiter. The garage geometry makes it essentially impossible for us topush a car uphill to the street to jump it. Now The Brat left her Echoin the garege for a month or so and it went dead, too. So I figureit's time to buy a real charger. Went to Kragen Auto Parts and boughttwo (one for here, one for Truckee) chargers. They are all "smartchargers", namely switchers with electronics, these days.The battery is really dead, 1.8 volts. The first charger hums andoutputs nothing. Tried the next one: it hummed for maybe 3 secondsthen sparked and smoked inside.Went back to Kragen and traded up, two better chargers. Neithercharges... no current, battery steady at 1.8 volts. Both have their"charging" LEDs off and "charge complete" LEDs lit.Back to Kragen, 3rd time, got all my money back. Passed by Bob Pease'splace all three trips, same collection of rusty VWs everywhere.A charger that puts zero amps into a dead battery does that by design,and there's only one reason to do that: to convince people they need anew battery. Kragen's sales pitch was exactly along those lines; "Ttwon't charge, so all the cells are shorted."So I went to work and nabbed a cute little Lascar bench power supply.It current limits at 1.2 amps, so I just cranked it up. The batterywent instantly to 16.5 volts, then settled down to 12 or so in a fewminutes, and is creeping back up. Interesting.So I guess I'll buy a couple of 3 amp or so lab supplies, with nicevolt and amp meters, instead of battery chargers. They're handier tohave around anyhow, cost about the same as a "good" charger, andaren't booby trapped.What Kragen is doing is fraud.John

Sep 28, 2009 42 Replies

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Joerg 16 years ago

Similar when I was in school and elected to use my bicycle instead of the bus, because that only ran once an hour (no school busses there). Getting home I had two options. Switch to low gear and risk breaking the chain or a crank connector, or hop off the bicycle and walk it up a hill.

Me too, used my bicycle every day about 4 miles to the university which was across a border. Sometimes I cycled around 20 miles to Maastricht in southern NL. Energy-wise it made no difference and the fuel for that trip was usually beer :-)

Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.

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Jim Thompson 16 years ago

Make it a Nissan and you've got it right ;-) ...Jim Thompson

| James E.Thompson, P.E. | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona 85048 Skype: Contacts Only | | | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at http://www.analog-innovations.com | 1962 | Coming soon to the elementary school in your neighborhood... I pledge allegiance to Dear Leader Barack Hussein Obama and to the community organization for which he stands: one nation under ACORN, unchallengeable, with wealth redistribution and climate change for all.

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JosephKK 16 years ago

What is the sound of one hand clapping?

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