Battery Maintainer - help please

[Guiseley]

A question for those with more elec trickery knowledge then me - and that doesn't exclude many of you trust me.

When I didn't use my motorbike for awhile I left it connected up to a battery maintainer.

I have two and wonder if they are beefy enough to be useful against a bigger car battery.

One is a Ring smart battery charger - and it says 12v 1.25 Amp.

The other is an Optimate 4 - and it says 12v 0.8A - suitable for charging batteries from 2 to 30Ah and maintenance of batteries from 2 to 50Ah.

Gobblegook.

Help please

 

[Mad Professor]

Optimate works fine -i had one
Bottom line if the green light comes on then its obviously charging and maintaining it it fine

 

[Guiseley]

Still researching - not sure if the Optimate 4 is sufficient as the battery is Capacity - 85Ah : CCA (EN) - 800A

Whereas the bike battery that the Optimate 4 was bought for was only Capacity Rating: 8Ah : Cold-Start Performance CCA (EN): 135A.

So there's quite a gap!

 

[PerryGunn]

I know a number of people use the CTEK XS 0.8 as a battery maintainance charger - that has a maximum output of 1.2A

The smaller chargers may well be unsuitable for completely recharging/reconditioning 80Ah+ batteries but, as a maintenence charger, they're not expected to do this, all they're doing is keeping the battery topped up and as long as their output is greater than the car's parasitic drain there should be no problem

 

[srhutch]

Think my CTEK is only 0.8A. As Perry says fine for keeping the battery topped up, but would take forever to charge from flat.

I got one when my old zed went flat after not using for a few weeks. Current car gets stood up for 4 months over winter and up to a month at a time the rest of the year and never had a problem.

 

[A1GSS]

I've got a mid range Ctek charger, does have a trickle/maintenance mode for low current charging, but will condition and charge batteries very well. Great thing.

 

[Guiseley]

Cheers all.

Sounds like I've got two decent maintainers then, but not something capable of restoring an 85Ah battery if it gets discharged. Sounds like I might get myself an 8A or 12A charger.

 

[jaq03]

I bought CTEK 3600XS few years ago. It charges both bike and car batteries with 0.8/3.6 A

Read somewhere that, if you use too low amp to charge, you end up ruining battery (?)

 

[sk93]

pretty much what everyone above says..
if it's just for maintaining, then as long as it's got a higher amperage output than the draw on the battery, it'll maintain it.
It'll also slowly charge the battery, but if it's not a sufficiently high enough output, it'll take a very long time to charge.

Basically, battery maintainers are low-amperage battery chargers (trickle chargers) with a bit of logic in them to ensure they don't overcharge and thus overheat.

I'm guessing that running one built for a max 50ah battery on a 85ah battery will still be fine, but the auto on/off logic built into the maintainer won't be perfect (eg, it won't accurately detect when to turn on and off, which could result in large "swings" in the actual charge of the battery, meaning the battery could be a bit low at times, and a bit overcharged at times.)

All said and done, I still think they would work "fine", as they're unlikely to get the battery too warm/overcharged, and unlikely to let the charge fall to a too low point).

as I say tho.. this is guesswork/theoretical and MAY be wrong

 

[Guiseley]

Cheers buddy - have decided to splash out on a CTEK that's rated for the battery in the Evora. So will now have three maintainers should I ever get a garage large enough to hold that many motors :wink:

 

[firebobby]

Also have the Ctek, great bit of kit and it's brought many dead batteries back to life.