OT: Lead Acid Float Charger

Many modern electronic chargers will not put current into a dead battery. I suspect it's part of a scam; car parts places sell you such a charger, it doesn't work, you come back, and they sell you a new battery.

I keep a cheap bench power supply at home and another one up at the cabin. It's good for all sorts of stuff.

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John Larkin         Highland Technology, Inc 

lunatic fringe electronics

They have. It's called a "death ray". Something to do with the large amount of energy it would need to deliver. Invented and patented by Nikola Tesla in 1907:

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Jeff Liebermann     jeffl@cruzio.com 
150 Felker St #D    http://www.LearnByDestroying.com 
Santa Cruz CA 95060 http://802.11junk.com 
Skype: JeffLiebermann     AE6KS    831-336-2558

Jim wanted the best:

Methinks buying a charger that can do float charging, but also has all the controller, monitoring, metering, sensing, and shutdown circuitry necessary to protect the charger and the battery, is a good investment. Yes, it's overkill, but methinks worthwhile. For example, check out the local marina or trailer park and see if they use cheap or small chargers? Some do, but they don't last. Eventually, most boaters and campers end up with much higher end chargers. I've gone through that experience myself, with marine electronics and mountain top generators. I gave up on low end junk long ago.

I'll go into more detail on what can go wrong later. Gotta run...

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Jeff Liebermann     jeffl@cruzio.com 
150 Felker St #D    http://www.LearnByDestroying.com 
Santa Cruz CA 95060 http://802.11junk.com 
Skype: JeffLiebermann     AE6KS    831-336-2558

Trickle charge is a fine way to kill batteries.

There's not a lot of difference between float charging and constant-current trickle charging. A car battery might self-discharge at something like 100 mA average, so pushing in 150 shouldn't do much harm. I guess the issue might be temperature if the heap is parked outside.

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John Larkin         Highland Technology, Inc 
picosecond timing   precision measurement  

jlarkin att highlandtechnology dott com 
http://www.highlandtechnology.com

I had just the opposite problem yesterday. I used the truck to jump the battery on the lawn tractor. Don't know what happened, the tractor started a couple of weeks ago, after not having been started over the Winter, but its battery was dead as a doornail yesterday.

Trickle charging for 6 months will leave a non-conducting layer where you dont want it. Using a 24hour timer to charge for 15 minutes/day is better. Using a smart charger to start charging when the battery is below 70-80 percent, is even better.

He could also get out and drive it around the block now and then. Pick up some fried chicken maybe.

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John Larkin         Highland Technology, Inc 

lunatic fringe electronics

was about to suggest it...

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  \_(?)_

On Thu, 31 Mar 2016 23:47:48 +0200, Sjouke Burry Gave us:

The cheap shit you have experience with, sure.

Since you're killfiled by JT, here's a link to a cheaper one.

The _self-discharge_ of a lead-acid battery is 10-35mA when _new_.

Besides this is a pick-em-up truck with no clock ;-) ...Jim Thompson

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| James E.Thompson                                 |    mens     | 
| Analog Innovations                               |     et      | 
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| Voice:(480)460-2350  Fax: Available upon request |  Brass Rat  | 
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           The touchstone of liberalism is intolerance

I blame lawyers, for tying to protect a few idiots from themselves.

There's nothing hazardous about charging a zero-volt car battery. And contrary to the opinion of the experts at Cragan Auto Parts, a zero-volt battery is not permanently dead.

I returned the stupid charger and got my money back. I found an old DSL wall-wart and put a belt sander in series to keep it from frying, ran that for a few hours, and it started up. Now I keep a power supply around.

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John Larkin         Highland Technology, Inc 

lunatic fringe electronics

On Fri, 01 Apr 2016 20:15:07 -0700, John Larkin Gave us:

Some that are taken to zero cannot be recovered, and that is actually usually the case. Deep cycle marine, etc. batteries are more tolerant.

But for the most part, one should not allow it to happen.

It isn't designed for zero volts detection. It is designed to prevent some fool from connecting it backwards, and causing the battery to boil over or even explode. Have you ever seen the damage cause by a battery explosion under the hood of a car? I have. You can't flush all of the acid out, so over time it cause a lot of rust, and it weakens the steel, if it is in contact for very long.

Early car battery chargers were just a light bulb in series with a rectifier that was lugged into a 110 volt outlet. No protection from electrocution, at all. They were quickly removed from the market, because they caused a lot of battery damage, and injured enough people to be declared unsafe. My battery charger is home brewed. I bought a new surplus battery eliminator for motorhome, and a 10A variac. I mounted them into the aluminum case that was from a scrapped W.W.II RADAR receiver. I built it while I was in in high school, and it is still working, over 45 years later. I can set it to any initial charge current, and I can plug it into a timer if I won't be right there while it charges. It isn't pretty, but it is very reliable.

The parts-store electronic chargers are switchmode and reverse protected. And current limited. And won't put current into a dead battery. That has to be by design, which could be deliberate design or very stupid design.

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John Larkin         Highland Technology, Inc 

lunatic fringe electronics

I didn't discharge the battery on purpose.

It worked fine for another year, when I sold the car.

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John Larkin         Highland Technology, Inc 

lunatic fringe electronics

Den 30/03/2016 kl. 22.07 skrev Jim Thompson:

The best charger is this:

CTEK Battery Chargers Are Trusted by Top Brands:

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But be very careful when connecting a power source to your car. The car electronics do not like power glitches.

The foreign accumulator should be activated "slowly with e.g. Power MOSFETs.

How about a home made Jumpstart accumulator consisting of four M1A 3,2Ah A123system cells with heavy duty wires and connectors?:

A123 Worlds Smallest VS. "Strongest" 12V Jumpstart battery:

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"Wrong question?"

Choose LiFePO4-accumulators instead with UnderVoltage-cut-off - I admit that they are expensive:

Mar 24, 2014, NEC to buy A123 battery systems unit from China's Wanxiang:

60Ah:

Bases in USA:

A123Systems - this is for the M1-cell:

Quote: "...Curent test projecting excellent calendar life: 17% impedance growth and 23% capacity loss in 15 [fifteen!] years at 100% SOC, 60 deg. C..."

September 2008, Phenomenal positive revealing Sandia-test:

Quote: "... Test results have indicated that the LiFeBatt battery technology can function up to a 10C discharge rate with minimal energy loss compared to the 1 h discharged rate (1C). ... The majority of the capacity loss occurred during the initial [!] 2,000 cycles, so it is projected that the LiFeBatt should PSOC cycle well beyond 8,394 cycles with less than 20% capacity loss. ..." Quote: "... [See graph pdf-page 23]

..."

PERFORMANCE OF PHOSPHATE LITHIUM-ION BATTERIES IN MOTIVE APPLICATIONS

Quote: "... On the other hand, a common high capacity rated cobalt lithium-ion cell is unable to maintain anywhere close to its original capacity. The cobalt lithium-ion cell may start out at a higher capacity, but it quickly loses its capacity after several cycles. However, the phosphate lithium-ion cell is able to continue cycling well and maintaining its capacity. ... Current test data on a cell level shows an expected 2000 cycles to 80% of original capacity...The battery can now match or exceed the life expectancy of the electric vehicle itself. ..."

LiFePO4-accumulators are secure compared to standard Li-ion:

Nail penetration testing A123 Li-ion:

September 21, 2008, LiFePO4 Batteries: A Breakthrough For Electric Vehicles:

Quote: "... Here?s a list of all the advantages of LiFePo4 batteries: * Safe technology ? will not catch fire or explode with overcharge ... * Does not suffer from ?thermal runaway? * Can be used safely in high ambient temperatures of up to 60C [Celsius] without any degradation in performance ... * Can be safely rapidly recharged ? when fully discharged can be brought to a state of over 90% fully charged in 15 minutes ..."

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Standard Li-Ion:

Exploding Laptops on Good Morning America:

Nail penetration testing Standard Li-ion:

Modify Li-Po Battery Nail Penetration Test:

Lithium Polymer Battery Explosion's (liposack):

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Lead-acid accumulators are not designed to be used:

Standard lead-acid accumulators works for 50-100 full cycles:

Quote: "... The cycle life of sealed lead-acid is directly related to the depth of

with respect to the depth of discharge is:

• 50 - 100 cycles with 100% depth of discharge (full discharge)

• 150 - 250 cycles with 70% depth of discharge (deep discharge)

• 300 - 500 cycles with 50% depth of discharge (partial discharge)

• 800 and more cycles with 30% depth of discharge (shallow discharge) [three years?] ..."

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Have not seen these LiFePO4-accumulators yet:

11 March 2009 Lithium batteries charge ahead. Researchers demonstrate cells that can power up in seconds: Quote: "... That seemed to be the case for lithium iron phosphate (LiFePO4), a material that is used in the cathode of a small number of commercial batteries. But when Ceder and Kang did some calculations, they saw that the compound could theoretically do much better. Its crystal structure creates "perfectly sized tunnels for lithium to move through", says Ceder. "We saw that we could reach ridiculously fast charging rates." ... The authors helped the ions by coating the surface of the cathode with a thin layer of lithium phosphate glass, which is known to be an excellent lithium conductor. Testing their newly-coated cathode, they found that they could charge and discharge it in as little as 9 seconds. ..."

br,

Glenn