That is what I was thinking. I know the sellers claim these batteries come precharged but how does one know when that was? I am so sick of battery issues. I just want one that will not crap out on me in less than 2 years. I could understand it if I did not maintain mine with a tender.

 

I've found that the best life comes if you keep them topped off but not continuously on the charger. I charge all my "summer" batteries 3 or 4 times during the winter and get what I consider better than expected life. I put a battery in my Thunderbird in 2012 and it was still going strong when I sold it last fall, over 6 years later. It was a Power Tec AGM battery.

 

That's the whole point of a tender, it's not a constant charge, it only does what's needed to keep it optimum. Batteries are so inconsistent it seems. I got 10 years from my factory HD battery, which was always on the tender. Then others say they only get a few years.

 

In the 80s and 90s, and into the 2000s, I never had any issues with car or motorcycle batteries. In the last 10 years, I have had car and motorcycle batteries crap out on me well before they should have.

 

Any time the battery is subject to a voltage higher than the nominal voltage of the chemistry (about 2.1 volts for lead-acid technology) it is charging. Tender manufacturers call this "float charge". It is my experience that batteries last longer if you do not apply that float charge over long periods of inactivity. I used to leave them on the charger all winter long and had several that were dead in the spring. Never had that happen with my current process. (Now I've probably cursed all my lawn tractors, bikes, and the Benz...)

Another reason for not keeping them on all the time is, according to a fire fighter friend, the number one cause of garage fires is battery chargers.

 

Yes I can remember back then I would buy a Diehard battery for a car and never have to think about my battery again.

 

I think we can all agree on that. But, why is it, with all the advances in battery technology, they still "just don't make them like they used to"?

I remember when you could buy a Deka aircraft battery for about $60.00 and it lasted 10 years. Now, Deka is out of the Aircraft business, an equivalent battery costs $250 and you're lucky if it makes it to 3 years.

 

My friend Larry's house. It was started by one of those portable battery boosters he had in his garage.

 

Damn! I have 3 tenders running 24/7...one on my Corvette and one each for the two Harleys...

 

To clarify, the house fire above wasn't from a tender, it was from a booster used for jump starts. I Googled "battery tender fire", there doesn't seem to be a problem with them.