Will this charger work on a completely dead battery?Can you use this as a power supply?
260867
This charger will charge a dead battery provided the battery is not broken. I put a dead battery on the Schumacher for 30 minutes and then switch to my 'automatic' battery charger to finish the charging as it will stop when the battery is charged, but the Schumacher does not. I do not understand using the Schumacher as a power supply. It's a battery charger.
260868
This is a manual charger, I have used it on all most dead batteries, it should also work on those completely dead. Automatic chargers will not. As to the use as a power supply, I have not tried that, but my knowledge of electronics tells me, it will supply the voltage and current, the voltage will be unregulated and unfiltered.
260869
Using this as a "power supply" is not recommended with sensitive d.c. electronics (radios, test equipment) and such. Car battery chargers don't have "clean d.c. output filtering. But you can attach charger to an auto/marine, etc. type battery and then connect to the battery then. The battery acts somewhat like a filter and your current should be acceptable. I've only done this in an emergency 2 or 3 times in the past 50 years, but it works. Otherwise straight out of the charger could damage "high end" electronics. Straight out of the charger to a radio, you'll probably notice an over bearing loud Hum coming from the speakers, that's unfiltered d.c. Good luck in your experimenting!!! Using this as a "power supply" is not recommended with sensitive d.c. electronics (radios, test equipment) and such. Car battery chargers don't have "clean d.c. output filtering. But you can attach charger to an auto/marine, etc. type battery and then connect to the battery then. The battery acts somewhat like a filter and your current should be acceptable. I've only done this in an emergency 2 or 3 times in the past 50 years, but it works. Otherwise straight out of the charger could damage "high end" electronics. Straight out of the charger to a radio, you'll... » Read More Using this as a "power supply" is not recommended with sensitive d.c. electronics (radios, test equipment) and such. Car battery chargers don't have "clean d.c. output filtering. But you can attach charger to an auto/marine, etc. type battery and then connect to the battery then. The battery acts somewhat like a filter and your current should be acceptable. I've only done this in an emergency 2 or 3 times in the past 50 years, but it works. Otherwise straight out of the charger could damage "high end" electronics. Straight out of the charger to a radio, you'll probably notice an over bearing loud Hum coming from the speakers, that's unfiltered d.c. Good luck in your experimenting!!! « Show Less
335676
I did try doing just what you described because that sounded like a really nice feature if it would work. UNfortunately, no you cannot use a charged battery in the charger to power another device.
229972
No... but if you are talking about a battery that had the lights left on overnight and 'dead' it will not charge if it is below (I think 2 volts) some minimum voltage left in the battery. It IS very frustrating because the older 'not so smart' chargers would at least try to charge a dead battery where these smart ones won't work at all. I faked one out once by connecting a small motorcycle battery to my dead car battery and fooled the 'smart charger' to start working and then put the motorcycle battery back. Battery was fine after about 6-8 hours of charging.
813422
If you are asking "can I use this to power a battery charger" the answer depends on what the charger needs for power. There should be a label somewhere on the charger listing volts and amps. If the label lists 12VDC and no more than 1 Amp or 1000 ma then this power supply will work. If you are asking"will this work for my 12V battery charger" the answer is no. You need a power supply rated at 14.5V to charge a 12V lead acid battery.
1403103
I can only answer for the one that I own. I can plug it in and it runs just fine, especially when battery is low. If your battery is completely dead, with no chance of ever charging again, it probably has a short and it, theoretically, will NOT work when plugged in either due to the shorted battery.I hope somewhere in what I said you find the answer that you were looking for.
1043529
You should be able to charge these batteries, but get ready to learn you wasted money for crappy batteries... Most of the "high power" batteries I came across are fake and not holding more than half charge they promise. Only brand name batteries like Eneloop and Duracell were performed exactly as specified. Another problem with off brand batteries is self-discharge. I had several batteries losing up to 70% of charge within one month. On the bright side with this charger you will find-out what batteries you can trust. Good luck!
804304
True, Like any rechargeable item charging it once it is completely dead will prolong the battery life to its fullest.
1083337
On paper it should work. In reality, this charger never powered on to charge anything.
1337709
Yes it will work. You just need to unplug the USB end from the wall plug and use the USB portion only. I haven't tried a full charge but it definitely gets you through in a pinch. It is a very handy device to carry with you at all times, I even use it to charge my cameras. That has been a real lifesaver for those special moments you don't want to miss because of a dead battery. Give it a try I think you will agree it comes in handy just when you need it most. TC
1092915
Unfortunately, the adaptor will not power the unit. It will only charge the battery.
2243842
Yes, just like any other charger but you can leave it hooked up after charging is completed. If the dead battery is no good, nothing will help.
1299179
Yes, it'll work but don't expect it to charge it all the way. Probably just a little emergency battery backup.
2263798
Wont work as a power supply.....only a charger.....it will recharge the laptop battery and then turn off
1171804
No, it will not charge the dead battery. This device gets its power from car battery so it could charge your other electronic devices like cellphones, tablets, etc. If your car battery is dead you need to jumpstart it or get battery charger.
1690207
I really really really want to flame you but I won't. The adapter whether it be the car plug or anything else is to power the unit and power the unit only. It will automatically turn on when it has power and when it loses power it will then prompt you that it will shut off in 10 seconds unless you tell it to rely on the battery power. So the unit itself is NOT a battery charger and will rely on the external power source first and once that external source is cut it will rely on battery power.
1478799
Hi There, the charger has a USB output which will send power to any device that has a usb charging port or can charge with a USB adapter. If you have a battery charger that will accept power from a USB adapter cable (i.e. one end fits into your battery charger, one end is USB) then it might work for ya. It's basically a big backup battery designed for charging devices, not necessarily batteries. However, you may be able to make that work if you have a battery charger that meets the above requirements.
400450
It wont charge anything. It'll connect, but not enough juice to power anything at all, even when plugged in. Don't buy it, mine just collects dust.