Charging Dead Battery

How about calcification buildup on the battery plates? I’ve heard if that happens then the battery can NOT be salvaged ….?

Good video. Noco Genius smart chargers have a force mode to charge a battery below 1 volt. I still have and use my Schumacher 1 Amp manual charger to trickle charge my battery along with my PulseTech PowerPulse passive battery desulfator.

Use the really cheap 9volt battery out of that old transistor radio, or the smoke alarm. Get a set of tiny alligator clips and parallel the 9vt to the clips when you hook up to the 12 volt you want to charge.
Better than being hunted down by "she who must be obeyed" cuz you drop her battery on the cement and crack it, woe - u in trouble plenty.
When you are done, tuck that 9vt and those gators in a baggie and tape them to the top of your charger.
Now you can tell the guys you upgraded your charger to a HEMI 😅

I’m totally confused!! Need help charging golf cart batteries but you lost me.

You talk to fast.
Where you from?

Heaven forbid a world run by “smart” computers, dudes like you make the world go round and you just saved my bacon 👍🏻👍🏻 thanks man🎉

This will work in a bind. Just be aware of the dangers.

There is a good chance that you will blow the fuse in your tool battery. The dead lead acid battery will more or less work as a short if it's completely discharged. The fuse is not easily replaced so you risk bricking your tool battery.

A better way is to buy a small 13.8V power supply (or 12V will work as well), preferably current limited. Hook it up with the correct polarity and charge manually for a few minutes. Usually it's enough to get the battery above 2-6V for the smart charger to start. You can get one for less than $20.

As pointed out in several of the comments, your battery will never be the same after a deep discharge. Lead acid batteries should be stored fully charged in a cool dry place. Disconnect it if possible and charge it fully with a smart charger or if thats not possible, arrange so you can charge it fully at the end of the season and top up the charge every 6 months. A permanently attached battery connector with an inline fuse is a good solution.

Bro, your method worked perfectly to jump start my 12v 7ah dead batteries! Preciate it!! Im redneck too btw. Cheers!

Thanks I'm a widow trying to learn all this stuff my wonderful husband took care of.

Thank you for this video. I used my car jumper to start my trickle charger and it worked. Now I can try and charge my 3 other dead car batteries I have lying around

It doesn't work on a battery that won't hold a charge lol, it will charge the battery enough to start but if left charging overnight it will of course be able to start, but if not hooked up the battery will not hold a charge if not hooked up.

Does the Harbor Freight charger you have not have a manual override button like the Noco Boost chargers have? If your voltage is under 2 volts, it wont recognize the battery.....then u press the manual button, and it'll read it then.

Worked perfectly… but I used a jump starter as fake charge hahahhaha great thanks

"we're gonna let that 19 volts cuuuuuum..."

👍👍👍 I hooked it up using a dewalt battery pack as shown and my charger kicked in! thank you very much. That is truly a hack! Now I'm going to do a video to show you how to get that mower and battery cleaned up nice. ..and yes, this comment comes to you 3 yrs after you posted the vid!

Dude you just saved me a DeWalt battery I just assumed it wasn't any good and it's been sitting on the shelf for awhile came across this video and thought I'd give it a try totally worked

Thank you Sir! I really dislike these smart things..bought a centech from harbor freight today with a completely dead battery on my RV. This trick took it 10 seconds to start working. Off an old DeWalt battery for a drill. Bless Ya! I was about to return it tomorrow with a frown on my face.

I threw away a whole set of batteries because I didn't know this :( Now I KNOW! Thanks!

Great tip man... Got it working!!! You're a life saver...

Worked like a charm! I thought something was wrong with my charger. Had NO IDEA that it was because it could not register a dead batter to even begin charging it. THANK YOU!!

Thank you very much. I am going to jump my lawn mower battery with my car :)

Picked up that exact charger at Harbor Freight in Raleigh Friday. Used a weak (but still 12.5v) alarm panel battery to get it started charging the 6 month old battery in one of my motorcycles. Rode the bike three weeks ago today. Went ride it Tuesday and it was so dead speedo lights wouldn't come on.
Anyway. Left charger on for two days. It's showing it is charging. Took it off this morning to go for a ride. Tried the key. Nope. Nothing. Meter battery. It's at 31mVdc. It was at 5vdc before I put the charger on it. I don't get it. Heading out now to get another battery.
I bought this one new in October. And it was fine 3 weeks ago. No aftermarket anything to be draining it. Irritated. May as well get the $55 back for the charger, too.

Was looking for info on battery chargers and now I'm more interested in if you turned the lawn mower into a ratrod?! 😂🤣

If you know what a smart charger is (That you didn't though your old el cheapo HF battery charge actually is 1!) and you run into this problem frequently, all you should do is hack into the charger and create a temporary jumping switch s.a. those push on switches (As someone else has uploaded a clip here on YT about it) and have the smart option to overrule the smart fracture you have but don't want, smartly!

Thank you, I needed to know this, and didn't.

Are you sure it's her drill battery?

Smart charger is not very smart

What about portable car chargers, please?

Happy New Year 2023! On the other end of "Lockdown". Unfortunately my Snowmobile Starter Battery that hasn't seen much action since early 2020 or 2021. Which means 2-3 years of not running.

Apparently there was enough juice for my "Smart" Chargers to attempt charging (usually 1-2 volts is all it needs)... BUT my Digital Load Tester which can give me a "baseline" reading needs A LOT more Volts. (I'm speculating 8-9 volts? Since after some brief charging it was showing 6-7 volts on a Multi-Meter but nothing on the Load Tester.)

After leaving it overnight it was able to "top off" and appear "full" (over 12v even 12.5/12.6) but the Internal Resistance is crazy high so the best I could be for a beginning/"baseline" was 75A, now about 115A but not much more yet. (Only a slight click/spin with the current onboard battery, Needs a jumper pack to provide the needed amps... Or a manual rope pull)

Thinking I need to put on a "dumb" charger for a while to force a charge... The smart Chargers "desulfate" functions and/or modes haven't seemed good/fast enough.

Maybe 20 minutes "dumb" cycles alternating with a "smart" cycle (cool down)... Load Testing before and after each step?

Sweet. Good job!

Damn John I’ve owned this damn “smart” Charger for a year and I thought it was harbor freight junk. I can across this video and it just so happens I left the fuel pump on and killed the battery in my truck and off course my jumper park was all but dead I did what you said and sure enough the charger started charging! 😊 thank you man

thanks im going to try this

Fixing to go trick my smart charger now and show it who's smartest one is 😆. Thanks

Good deal. I was going to buy a trickle charger but this will work. Thanks👍

I'll be trying this later today on my motorcycle

Awesome trick. I left my car in the garage for half a year not able to charge at all. Now it is charging and hopefully my car will go back online soon. Thank you for sharing

Hey where can i find or get those lead cables you connected to the secondary battery? Or what else can be used to deliver the same result

I have the same charger and my charger keeps going from charging to fully charged what does that mean

Thank you saved my camping weekend!

Genius after returning one thinking i got a dud for the second time i tried your trick and got it

Awesome video it actually worked.

thanx john..

Thanks,worked great

It's so smart it's stupid!

So.. the smart battery charger is actually stupid battery charger. Is it not..? Better change the name to stupid ya..

Thank you so much for the tip. Worked great.

Jon your a legend with this video 🙌🏼

You saved me

You look just like someone I worked with at a car dealership. I got fired first and he got fired later for lighting a kid on fire using brake cleaner.