Old batteries that don't hold a good charge

[dsiekman]

With the two dead batteries, try smacking them on a hard surface several times on each side. Not hard enough to damage the case, but just a good whack. Sometimes that will knock the oxidation off the plates and buy you a little extra time.

Do this at your own risk. I am sure the manufacturer would never recommend it. These are similar to the batteries in security systems and Fios boxes. I had a phone tech tell me out this several years ago. It worked for me.

[archeryrob]

that is what kills all lead acids. They clean the fluid and remelt the lead to make new batteries when recycling them. Its the corrosion that kills their charge holding ability.

[john from md]

Almost all of the small 5/7/12 amp batteries that you buy today are Absorbed Glass Mat batteries. The electrolyte is absorbed in the plates allowing you to mount them in any position. These batteries differ from Gel Cells in both charging voltage and how they are stored. Both of these batteries need "smart" chargers in order for you to get the full life out of them. The charging rates vary automatically so that the cells are charged fully and without warping. It is also a good idea to charge them every couple of months when they are sitting.

I rotate my 5 amp battery between the garage door opener and alarm system both of which have "float" charge systems to keep the batteries at top charge.
I would suggest buying a NOCO Genius G1100 or CTEK multi US 4.3 both are much better than Schmacher these days. If you have a Deep Cycle battery for a trolling motor, I would get at least a 7 amp version if you want to charge it overnight.

Regards,

John

[buzz]

A smart charger is definitely the way to go.

For an example, consider the average home alarm system. Inside the metal box that comes with every home alarm system is a small 12v battery. These batteries are connected 24/7 to the main circuit board of the alarm system. In the event of a black out it powers your alarm system, but under normal conditions the alarm circuit also monitors the battery condition and trickle charges it as necessary just like a smart charger.

I just checked the one in my alarm system yesterday... reads 13.4 after 10 years in use.

[john from md]

Buzz,

If your alarm battery is 10 years old, you should replace it. While it may still have the voltage, I doubt it will have the amperage to run your system too long if you have a power failur. Addtionally, the loud alarm, if you have one, draws more amperage than just keeping the system operating in the standby mode. It would be a bitch if a guy got your yak 'cause your alarm only worked for 30 seconds.

John

[archeryrob]

I agree, I work in the alarm industry and battery are to be replace at 5 years. They still hold voltage but will drop to noting on a load quickly. Most alarm batteries are your standard 12v 7ah battery.

[buzz]

Buzz,

If your alarm battery is 10 years old, you should replace it. While it may still have the voltage, I doubt it will have the amperage to run your system too long if you have a power failur. Addtionally, the loud alarm, if you have one, draws more amperage than just keeping the system operating in the standby mode. It would be a bitch if a guy got your yak 'cause your alarm only worked for 30 seconds.

John

I agree, I work in the alarm industry and battery are to be replace at 5 years. They still hold voltage but will drop to noting on a load quickly. Most alarm batteries are your standard 12v 7ah battery.

Thanks for the tip guys.
I'm in the middle of re-doing the system right now. Just canceled with the company that installed and monitors it and I'm reprogramming it. I'll buy a new battery for the alarm and try out the old one in the yak.