AGM and flooded may differ - in respect to maintaining "float".

Living off grid for many years I maintained a battery of 18 "T-105" storage batteries...

Once a month you charge to 15.5 - 16 volts at a low current beginning from 100% charge, An "equalization" charge...then top water as necessary...then a brief resumption of charge to stir electrolyte to avoid heterogeneity of solution ... Leave it alone the rest of the time.

 

When we first purchase our vehicles we bring them home and hookup battery maintainer/desulfator for for a good 24-48 hr saturation charge. Then each month I plug both vehicles on the tender to another good 48 hr saturation charge. All other batteries on motorcycle, mowers, tractors, skid steer stay on the maintainer. Never a battery problem.

 

apology due - because I'm oldtimey I forgot that all the new machines have 24-7 battery loads... complicates the issue, as it's no longer merely about battery but is about a battery under a light load... The battery UPS systems I maintained for the army (these supported a crypto-lab) held at the equivalent to values given below:

http://batteryuniversity.com/learn/a...d_acid_battery

https://en.wikipedia.org/wiki/Float_voltage

 

I don't like surprise failures. So, I replace vehicle batteries every 3 years. IMHO, it's good peace of mind.

I'm going to be not operating my quadra-glide for 2 weeks.l probably should put it on a tender.

 

I'm not sure this statement is correct with the newer AGM batteries. Checking the literature that came with a new HD battery and reading through the Yuasa Technical manual both say the sealed Factory activated are ready to install:

Most Yuasa AGM batteries are available either “factory
activated” or as a dry battery with an acid pack. A “factory
activated” battery does not require filling before installation.
An extensive activation process ensures complete absorption
of the electrolyte so no liquid acid is contained within the
battery. This process allows these batteries to be shipped from
the factory ready to install. The GYZ and YTZ series batteries
are only available as “factory activated”.

From HDJ01575 Battery installation:

General Battery Information
All Absorbed Glass Mat (AGM) batteries are permanently
sealed, maintenance-free, valve-regulated, lead/calcium and
sulfuric acid batteries. The batteries are shipped pre-charged
and ready to be put into service. Do not attempt to open these
batteries for any reason.

I'm glad Rockout mentioned the Yuasa brand, I went to their site and read most of the Tech. Manual and All About Batteries section, it will be a great reference for the future.


http://www.yuasabatteries.com/pdfs/TechManual_2014.pdf

http://www.yuasabatteries.com/index.php

 

Yes, this is true for some batteries, that they come 'pre charged,' however most people don't concern themselves with the date of manufacture. Between shipping, distribution and sitting on the vendors shelf for months if not longer, it is only prudent to bring it back up to full capacity before pulling copious amounts of current from it. No harm will ever come to a battery that is trickle charged, plus it only serves to prolong the battery's life span.

 

Agreed

Reading on the 2 sites I had to wonder just how long it will be before Lithium is the standard and what will be the new battery type after that?

 

My bikes are on Deltran Battery Tenders whenever they're in the garage. Just replaced the OEM battery in my 2003 Nightrain last summer. For the record, that's almost 13 years (12 yrs, 10 mos) of service before replacement. I have 4 Tenders, 2 bikes, 1 lawn tractor, 1 generator & no battery issues from leaving them connected when not in use.

 

Does 'service life' equate to percent of available charge capacity? Earlier Vernal mentioned something about only 80% of potential is achieved unless battery is pre-charged before use. What I'm asking is, does fully, slowly charging a battery before initial use make it last years longer (all other things being equal, like use of battery tender)? Or does it still fail about the same time as a battery not so initially charged, only with a bit more capacity at the end of its life?

 

like many products sold these days......they don't make 'em like they used to............