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As Miracle Max would say, there's two kinds of dead batteries, and there's a big difference between them. Mostly Dead This is the most common kind of dead battery. Let's say your battery is rated for 300 cold cranking amps. After several years of use, it degrades until it reaches, say, 250 amps. Your battery isn't out of power, it just can't get your engine ...


12

Those types of chargers are designed to provide short bursts of power to start a car, most do not have a battery charging mode. Once the car is started the alternator will complete charging the battery. Some of these chargers have a USB output for charging phones, but they don't have the capacity to charge a car battery back to full.


2

Looks like it's one of these: https://www.napaonline.com/en/p/NBP6535 Napa Type 35, 550 CCA wet cell battery If it was an AGM 35 it would be 640 CCA: https://www.napaonline.com/en/p/NBP983585 - Not sure on the months thing, possibly an indicator it has a 12 month warranty as standard - NAPA warrant their batteries differently according to the type: ...


2

"What are those called?" You are thinking of a battery tender. You can typically find them for under $50 (€46). They are sometimes refereed to as trickle chargers. I have never used either devices, but I think that in your case, the battery tender would be the better solution. A battery tender helps maintain the charge on your battery over a long period ...


2

A battery charging protocol defines a certain voltage and amps for a certain period of time, then raising voltage but lowering amps until finally tapering volts to prevent battery plate overheating. Older battery chargers just blasted in a set number of amps during the entire charging period. I don't think the protocol is the same for EFB and AGM. But you'll ...


2

In addition to limiting max voltage, EFB and AGM batteries require different recharging protocols. It's not like the old days. Now you must match the charger to the battery or you can damage the battery.


2

As long as the charger is rated for EFB, you don't have to worry about overcharging while in the vehicle. It's the older chargers that could output up to 18 volts that can fry electronics. Those should be junked.


2

Two possibilities: The battery indeed needs replacing. As you discovered, old batteries don't die by having reduced cranking amps; they die by having reduced capacity. Thus, the phenomenon you're seeing seems to be very similar to a dying battery. There is parasitic drain in the car. Something, some circuit, is left on even though it should be off. To ...


2

You are right, the procedure is to prevent sparks next to the battery, since the battery can produce a highly explosive hydrogen oxygen mixture while charging. Sparks are generated when you open or close a circuit while it allows current to flow. That is, if the charger is off, you will not get any sparks. If it is on, you will get sparks on the first clip ...


2

Miracle Max notwithstanding. There are a relatively few (more like very few) jump starters which directly start the vehicle with little or no involvement from the vehicle battery. Most jump chargers which advertise large starting current capabilities are marketing hype with about no relationship to reality. The majority of jump chargers transfer charge at a ...


2

Answers to your 3 questions: 1) No, there is no such "magical" device. If there were, everyone else would know about it too. When a battery is past the end of its service life there is no process to revive it. 2) Moot question in light of the first question. 3) I'm going to speculate that the initial test was faulty. The dealer likely charged the ...


2

I am going to be in the minority here, but I have had success jump-starting my SUV with a larger version of what you are showing only after letting it sit connected to the battery for 10+ minutes My car has a power drain issue that no one has been able to figure out in 7+ years. So I've needed to jump start my car frequently, so i bought a larger version of ...


2

While the answer by wilkvolk is accurate for recharging a battery, I'm pretty sure you won't need to go through all of that to do what you need it to do. If the battery is hooked up to your vehicle and is being recharged by your on board charging system (ie: alternator), and the on board charging system is functioning correctly, you shouldn't have to worry ...


1

Step 1 Wear protective gloves and goggles before you rebuild the cell structure of your 12- volt battery. You need to access the cell reservoirs that contain highly toxic sulfuric acid that immediately burns on contact with skin. Step 2 Place your 12-volt lead-acid battery in a battery tray on a stable work surface. Remove the six battery cell caps on top of ...


1

I learned long ago to not charge the battery but go directly for the engine (one contact to the postive pole and the negative to the enginge block to avoid damage from small flashes. not sure this is at all a good idea or even possible today, maybe someone with knowledge can evaluate?


1

If the voltage on the battery pack is higher than the voltage on the car's battery, it will charge the battery to some extent. How much depends on the voltage, capacity, and charge level of the 2 batteries. It is unlikely that the jump pack will be able to charge the battery enough to start the car without the jump pack. As others have said, the intended ...


1

There is a reason why a car battery is big and heavy, and the portable kits are not - they have not nearly enough power to charge a battery. But there is no need or use to charge a dead battery before starting the car - just jump-start the car, and once it is running, its alternater will load the battery just fine. It is a good idea to run the car for 15-30 ...


1

Battery tenders convert AC to DC electricity in order to charge the battery, this creates waste heat which needs to be vented to the environment, which is why there will be air holes or slits on the side or top of the tender. If you seal the tender or charger in an enclosure it will overheat and either break or a fail-safe mechanism will cut it off, this is ...


1

It looks different from my charger. But No, there is no way these chargers damage your battery, as they are in fact not chargers. The actual charger is on-board of the car. These ‘chargers’ are more safety devices that inform the onboard charger of the status and max current to draw via the CP pin. In some cases they do a few more checks. When all is OK it ...


1

I would like to understand if I need to disconnect the battery before charging it. If so, both cables or just the negative? Electrically, it does not matter. IF you want to disconnect, both cables, or just the negative is fine, but please don't disconnect just the positive because if you accidentally misplace the wrench between positive and chassis (ground),...


1

If the battery will not hold a charge, then it's already at the end of its life. It should be replaced right away or as soon as you plan on using the car again. As it is, chances are good that the car will not start the next time you need to use it.


1

Whenever they can be left unsupervised is stated in their manual. Both the big lithium pack and the wall charger can have "do not leave unsupervised" clause and you should respect that. Lithium batteries have a nasty tendency to catch fire for the slightest reason. Like overcharge, undercharge, overcurrent, overheat, etc. So, a failure of the control ...


1

Yes, generally you should be able to use any 120V equipment on the portable generator, provided you don't go above the maximum power rating. So yes, you can plug a battery charger. As far as leaving the generator in the sun, it should be specified in the operating manual.


1

When you have no option to keep your car battery topped up during storage. Your best option is to bring the car battery inside yor house to charge it there,You will need to charge the battery about once every month but this is if your battery is good. If your battery have started to go bad it is best to put on a trickle charger and have this connected the ...


1

The solar panel in your link is made to charge phones and other consumer electronic and have an output of 5 volts. To charge a car battery you will need a solar panel of 12 volts or more and to realy charge anything it will need to have an output of 4amps or more. A solar panel will only produce the rated output for about 8hrs in the middle of the day,so ...


1

A 100Ah battery will likely have a lower internal resistance than a 65Ah battery. That will mean that the 100Ah batter will try to draw more current when charging than the 65Ah battery. A good quality charger should be able to limit its maximum current to say for example 6A without any harm to itself or the battery. In that case it will take almost twice ...


1

No magical devices to bring a battery back to life.... except water if the level in low. Based on my experiences with dealers, a crooked service tech told her a good battery needed to be replaced. During the visits later on, you got an honest tech.


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