My new Battery Tender Plus gets almost too hot to touch during use. Is that normal? The battery shows 12.85v and the charger is still on the full charge mode (red light). Battery is a new Energizer Deep Cycle RV/Marine. My new Battery Tender Plus gets almost too hot to touch during use. Is that normal? The battery shows 12.85v and the charger is still on the full charge mode (red light). Battery is a new... » Read More My new Battery Tender Plus gets almost too hot to touch during use. Is that normal? The battery shows 12.85v and the charger is still on the full charge mode (red light). Battery is a new Energizer Deep Cycle RV/Marine. « Show Less
1938078
Doesn't sound right. Mine does not get hot and is fully charged with a green light. Sounds defective.
1938079
I'm sure you have a knowledgable answer by now. I have only use my Tender on my BMW car battery and have not had this problem. I have a another charger I use on my Marine battery and it takes a long time to go from charging to low maintenance cycle.
891206
Mine got uncomfortably hot too while it was charging my truck battery back up. I set it on a brick and actually let a small fan blow on it (which surprisingly cooled it off) But after 2 days like that, it reached a point where it blinked green, and eventually went solid green. And once it went green it cooled off - presumably drawing far less current. I'd guess your battery is fairly depleted and must be given some time to charge back up. If you are concerned or feel it's a safety issue - call the company.
1938080
Yes as the battery tender charges the battery up to the desired full voltage, a shunt circuit connects a resistive load across the battery in order to absorb the excess charging current. Which result in a dissipation of heat as excess energy is routed through the resistor instead of back into the battery.
1388662
It might, depending upon battery size and how discharged it is - if it is totally discharged, nothing may bring it back, but if it is just really low, you might try to pre-charge it with a regular charger and then maintan it ( which is what the Tender is for) wihe the Battery Tender. Remember, it is only 1.25 amp and I would think you might need at least 2 amps for charging very weak batteries
216483
Yes, that is normal. This charger gives a deep slow charge that just takes time. It will bring a dead battery back to life if the battery does not have a dead cell. I recommend it as a good deep cycle charger.
1651789
I will try my best to help you with your question. First the batteries need to be fully charged overnight. Next they should not be connected to any equipment in any way including ground. Next follow all the instructions for the testing procedure. When doing the test which is a very short time period as indicated in the instructions you will get the reading on the meter and it will change the longer you keep the load switch engaged, it will also get hot in the tester and smell also. This is normal as the tester is putting a 100 amp load on the battery and determines how long the battery can maintain its voltage. This is why you should not hold the load switch longer than the specified time. Use a watch to time the length of time that you keep the load switch pressed and keep an eye on the meter reading. If you have followed all the instructions to the letter and you still get a low reading I would take the new battery to a place like NAPA or Auto Zone and have it tested there. That way you will know if the tester is at fault. It is a pretty simple device and there is not much to go wrong with it. Just be careful handling the meter just after testing and hold it by the handle until it cools down. The other answers you received are spot on correct. " Slightly weak" does not give any of us the whole picture of the test being performed also it is highly unusual to find a new battery that is weak once it has been fully charged and put into service. Good luck. Harold
1943365
I noticed that as well. My old one was heavy. New one light. So, probably a more updated "solid state" charger. Voltage output is a little higher than my old one.
25764
Yes that is a problem on the first charge ! I used a 1.2 V battery tender for the first charge. You better invest in a smart charger, they are around 30.00. When you are not using the vehicle, plug in the charger. The battery will last a lot longer.............................................johan`
1124159
No, this is not normal. This model of charger is poorly designed and is overheating and melting its own case. It's a fire hazard and you should stop using it.
140767
The battery will not take a charge.Hook it up to a battery you know to be good.You should get a blinking green then a change to solid green.If the tender does the same red to green then the tender is probably faulty.
2252281
The batteries are sold partially charged. Your charger completed the charge by adding 670 mAH. What you want to use is the Refresh option which charges fully,then discharges, measuring the MAH of the discharge. It will do that several times, each time the mAH is a little higher. After a number of times, the mAH no longer increases and the charger leaves the battery fully charged. At that point, you use the Display button to display the mAH. For new AA batteries, it's slightly more than 2000 mAH. Bbefore you start all this, insert the batteries, then disconnect and reconnect the DC cable, then press the Current button repeatedly until the display reads 700 mA. That makes the charging current 700 mA, which is fine for AA batteries, and the charge-discharge cycle is much faster than with the default charge current of 200 mA. New batteries need this refresh cycling to reach their rated capacity of 2000 mAH. If you just use the discharge-test mode, you will get less than the rated 2000 mAH. Look on the Internet and you'll find all of the above and more.
1792489
I'm not sure, similar to other chargers it has a red blinking light while charging and a solid red light when charged. I have assumed that when the solid red light is on it stops the charge mode and doesn't continuously keep feeding juice to the battery. I've left several batteries on the charger for a week or two before and when I grabbed the battery it was not warm at all and I've not had any problems with the batteries.
2206610
Nothing, what should happen? The reason you shouldn't use it above 32 degrees is you could overheat the the element or the battery. I don't use it as a battery warmer. It operates at temperatures well over 32 degrees but you have to have enough of a heat sink to dissipate the heat or turn it off and on.
777234
There is no reference to desulfation mode on the face of the charger. There is a switch which allows one to choose between a conventional low-maintenance battery and a maintenance-free deep cycle battery. I would also tell you that my unit has been working well except the DC amp gauge stopped working the first day and I can find no way to get it repaired or talk to a knowledgeable representative. It has charged many batteries satisfactorily in this condition.
739702
I get 2 and not quite a 3rd full charge. I feel like the size of this battery is overstated. I previously had a battery charger that claimed to have 11000mHa. and easily got four full charges out if it. I'm not happy with this current battery charger at all.
1486252
My experience is, it does not get hot at all. I have two batteries on charge all the time in this, as well as one on the original charger. Based upon my experience - Yes it is defective.
1063154
I just started having the same problem. According to the manual here are some possible causes and solutions. Life of rechargeable battery has expired Insert a new rechargeable battery. Rechargeable battery is being charged or refreshed in temperatures either too high or too low. Charging and refreshing temperatures should range between 32F - 95F (0C - 35C). Charging incorrect types of batteries. Charge only a Ni-MH rechargeable battery.
445829
My battery tender stays connected all the time. It only comes on when the battery needs charging. It has a red and a green light to tell you what mode it is in. Solar energy used for charging should not make a difference.
223355
Well, most of the time high temperatures means way up in the 100s degree, I don't think anybody uses that battery charger in those hot temperatures, and the only reason they say that is because heat decreases the battery life, you are not gonna use that in high temperatures are you?