While I can agree that using the wrong battery tender or storage device can shorten battery life, as far as I am aware, Battery Tender branded devices are not meant for AGM batteries like the ones from Genius are... That could be a culprit... But being in Wisconsin and only getting 7 to 8 months of riding, tenders are a way of life. Nothing is worse for a battery then letting it fully discharge... I have had way better luck with the Genius maintainers then other brands with AGM batteries. Not all of them are created equal, and with the push for the new lithium batteries, the type of maintainer you use is even more critical

 

I used a battery tender (Deltran)on the AGM battery that was in my ricer, got 8 full years before it crapped out. Going on 3rd year on the AGM in my Limited, still going strong. I have heard that lithium batteries need a special charger, but I don't have one of those.

I don't think you need special chargers for AGM batteries.
Gel cells do need special chargers, but I haven't seen much of those lately.

 

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Ah,more good info & insight with respect to maint chargers vs battery srv'c life ,AGM and now Lithum bike batteries too that IMHO are overpriced & not that reliable either along with also not proving their supposed 2x longer srvc life stated by the mfg's vs other avg non lith bike batteries on the market today is even obtainable on a reg basis like they make it seem as though is the case .

With todays high quality high output AGM batteries avail for HD's today with 400/500/even 600cca's for $100-150 to your door vs a lith bike battery of = CCA costing a min of 2x-3x more more money just isn't worth it at this time.

I say that because lith bike batteries have yet to prove they can have consistent good reliability , good perf esp in colder temps where lith bike batteries fall short along with their stated by mfg 2x-3x longer srv'c life still needing to be proven to actually be obtainable with more then just few lith bike batteries that were tested under controlled lab cond vs real time testing of a lith bike battery in an HD getting plenty of vibration ,heat & temp variation running around someplace like AZ for a few yrs to get more realistic reliability & srvc life results of a newer gen lith motorcycle battery.

I realize that when space is an issue with a custom bike build thats where a lith battery makes more sense,but it doesnt make sense for the avg touring bike because of its 2x-3x more cost along with lith bike batteries also having to still prove they are consistently reliable and have 2x-3x more srv'c life on avg then lead acid AGM batteries do at this time too with price reduction before i'd consider trying one.

A while back Boeing aircraft mfg tried using new gen lith batteris on board the latest gen pass jet they had just introduced and guess what,the lith batteries in fact had issues when they were under the load they were specifically designed to handle starting on fire in the newer gen design jet they just released .

If i am not mistaken the fix was going back to AGM type battery design because they said it had proven reliability & safety while still doing the job they needed the batteries to do with more wt of the AGM battery tech being the only negative.

Scott

 

I think you should visit Battery Tenders web site or do like I did and give them a call 1-877-456-7901. I have a HD Super Smart Battery Tender, (made by Deltran for HD) and a Battery Tender 2 bank International charger. They have some very good information on their website under technical information and Battery Charging Basics. Before I decided to keep both of our bikes on a charger called to make sure the chargers were made for the AGM batteries and I was assured they were and keeping them connected for 3-4 months will not overcharge the battery.