I've had good luck with battery tenders (the jr.)
I'm using 5 up in my shop on tractors and 4 wheelers and the camper deep cycle.

Several of the batteries are 5- 12 years old and still starting the machines.

quote:

Originally posted by Nframe:
I've had good luck with battery tenders (the jr.)

The Jr.'s are good too. IIRC, they are .75amp, but still have the smart 3 stage charging. It just takes them a bit longer to reach the resting (float) stage.
 
ETA, Amazon sells the Junior for $25, and the Plus for $45, cheap insurance to maintain a healthy battery.
 

This message has been edited. Last edited by: henryaz,

Autos with sophisticated electronics are often a pita. I have a Corvette that goes dead if allowed to sit more than 7-10 days.

Great performance but some real misfires in design, like putting battery directly above the computer. Should the battery leak, the computer is destroyed. Must be designed by an MBA.

quote:

Originally posted by maxdog:
I have a Corvette that goes dead if allowed to sit more than 7-10 days.

Yikes. What model year is your Vette?

This all has me very confused. Apparently Toyota didn't get the memo about this.

My 2016 4Runner sits for WEEKS at time in an airport parking lot as I go gallivanting off here and there. I am still on the original battery and it has not failed to start for me from 100 to -20 degrees. And yeah, it has a plethora of computers.

My wife's 2016 Subaru Crosstrek has been known to sit for a couple of weeks as well while we were on vacation, and nary a problem with the battery.

This reminds me when I had my 3rd Gen RX-7.

It was my weekend car so I drove it maybe once a week when I went out or was not working. But usually if I didn't drive it every 3 days the alarm was such a power vampire that the battery would fall about 2 volts or so below the threshold to start the car.

So initially I would just pull one of the terminals when I parked it and reattached it when I wanted to drive it. Even if you tried to steal the car unless you knew that the battery wasn't connected you weren't going anywhere.

Wasn't until I got a garage before I sold the car that I figured out how the previous owner didn't have the same problem and he drove it every 2 weeks to 1 month without starting it. In the locked garage he didn't arm the alarm which also locked the car.

Could still lock the doors but the alarm would not work if it didn't have power.

Had a customer with a BMW that had a recharable key fob that charged in the ingniton but he went of the country for several months. The car battery was dead and even when he charged it couldn't start it since the key and fob were one unit. Told him call the dealer. BmW no longer makes those stupid fobs anymore.