colo63sw

This is a few questions for those that use a trickle charger. I am thinking of getting one and using it on my 93.

Do you disconnect the batt to trickle charge? Any badness that can happen if I don’t disconnect the batt?

Where do you connect the negative clip?

If my 93 has been sitting for 3-4 weeks how long will a trickle charge take to top up the batt?

Thanks in advance.

biggiefl

You do not need to disconnect the battery but if storing for more than a few weeks, I would. Depending on how low the battery is after 3-4weeks it might take overnight to charge it. I have had dead batteries and it only took overnight to charge.

mickey5

There's a big difference between a trickle charger that puts out a continuous low amp current and a maintainer that modifies its output based on the battery's condition. Storing your car over an extended period of time needs a maintainer.

auggy

Another way to go--- charge up the battery, disconnect the negative battery terminal, forget the trickle charger.

QCVette

Charge up the battery and then put a maintainer on it. You do not need to disconnect the battery cables.

I have read that the reason for charging it first before putting a maintainer on it is that the very slow charge may result in a reduced capacity of the battery. Charging it normally first removes that problem.

I have run maintainers for years in the winter storage on my C4's, C5's Impala, truck, even the tractors. C5's have a parasitic drain that is a common issue with discharging the battery. There are a lot of posts about putting a maintainer on. Some need it if only stored for a few weeks.

Maintainers work.

Good luck.

rocco16

I keep a Schumacher SC1 Maintainer on not only my Corvette, but on my riding lawn mowers, my motorcycles, and my boat. I disconnect the Corvette's ground cable when the maintainer is on it. Peace of mind, if nothing else.

I use to use the Deltran Battery Tender Juniors on everything, but as they 'expired', I replaced them with the SC1. Works just as well and is 1/4 the cost.

colo63sw

Thanks for the help.
I am not looking for a ‘maintainer’ that I am supposed to walk away from and forget. I am thinking of something that I can hook up to the batt the day before I plan to drive. My stable is kind of big and in 2 different garages so I don’t like a maintainer, even one that will charge 3 batts at once.

I don’t like the idea of disconnecting the neg terminal; I think the computer ‘resets’ & other not great things happen when the electronics loose signal. Correct?

Thanks again!

rocco16

Black and Decker makes a smart charger that will charge at various amperages, including 2A, and I've had good luck over the years with that charger. Schumacher make similar chargers.

I've never experienced any difference in how the car runs after disconnecting and re-connecting a battery. After all, you have to do it every time you replace the battery AND there are a lot of maintenance procedures in the FSM that start with "Disconnect the battery terminals.".

ghlkal

I use a battery tender.

FWIW

I do connect to the negative post of the battery itself.

I don't disconnect the battery for the same reason.

CE1

been using a battery tender for 10 + yrs and has lengthened the battery life, it will charge then maintain at low voltage to get rid of sulfation and save the battery plates for longer life. I mount the tender to the posts with the ring connections and leave the pig tail on when not charging, never had a problem. last battery for the Vette lasted 7 yr 3 months.

hcbph

I just disconnect the battery in my cars when in storage. I have a battery disconnect switch on the negative battery cable so 1/4 and it's either off or on. I do try and run the car every month or so to insure all the seals etc stay wet as needed. Been doing this for a lot of years without an issue. Only thing I've had any issues with is the radio loses it's programming but that's not a biggy for me.

thurman_merman

Having your battery run totally dead then charging overnight for a drive will kill it. Either get a deep cycle battery or get a maintainer. I use them on everything that I have and I don't have to prematurely replace batteries any more. I don't know why you wouldn't want one but it's the correct route in this case.

Edv92c4

This is the proper route to go. Op, why wouldn’t you want a maintainer? I too have a larger fleet that about 15 of my cars and trucks see minimal usage so the maintainers (2 of which will charge 4 batteries at once) have saved and prolonged the lifespans of many a battery for me. Simply letting a battery discharge on its own (either with or without parasitic draw) then charging up from weak or dead will definitely shorten battery life due to sulfation.

colo63sw

Thanks for all the replies. I am learning stuff here. Let me see if I got it right:

Tender & maintainer are the same thing: - they monitor batt & keep it topped up?
Trickle charger (old school) is dumb and just pumps in 1-2 amps until the batt won’t take it anymore?

Good to get the info on how not to treat a batt. I don’t think I am letting the batt go dead or discharge too much by letting the car sit for 2 weeks or even 3 weeks, but much over 4 weeks and I get concerned. The car starts right up with only ½ second of cranking if I wait for the fuel pump pressurize the system as I turn the key.

One reason I am looking for a ‘maintainer’ (OK you guys have moved me into the modern world) is that a normal drive to work and back gets the batt gauge barely to the ½ way point (drive is approx 8 miles of suburban traffic).

PS: One reason I am looking at the batt so carefully is that I look at the location and think ‘I don’t want to replace that battery!’

thurman_merman

You got it. The maintainer is as simple as park the car and plug it in, unplug it, start and drive away. It will come with a connector that you leave on the car all the time, there is no reason to disconnect the battery or mess with alligator clips.

auggy

The only thing I have encountered with removing the neg. terminal is losing the radio presets. I don't like the idea of something on all the time because of a slight risk of fire, plus with a constant charge you are going to have to check on the fluid level each year , otherwise risk of drying out. However, it might be suitable for many because driving habits, storage situation, fleet size, etc. No one size fits all. I do know that these cars have , what I consider, a hefty parasitic draw and doing nothing is the worst option.

aklim

True but I use THIS so that there is a cap on the terminals.

stingray71

I use the Battery Tender Junior - only about $27 on Amazon:


I didn't disconnect the negative terminal. I just connect the black clip to the metal of the hood clip inside the engine compartment. Works great.

colo63sw

Thanks for the suggestion! It looks like BT Jr. is the bare minimum, the fine print says it will not charge a car batt & is not applicable for anything bigger than a car; -SUV, truck, etc.

Thanks again.

Paul Workman

The BT Juniors (I've had them for 16 years now) put out a max of 800mA, which is more than enough to supply normal parasitic load (25-50mA) and the normal internal discharging and consequential sulfate formation at bay. However, the BT Jr is NOT intended to recharge a discharged battery, practically speaking. Oh, it will, given enough time, but that isn't there purpose in life. Keeping the battery fully charged, AND preventing sulfate formation and thus service life...IS their purpose.

If a battery has become discharged, then a battery charger is needed. I have a Black and Decker "smart" charger that can be set up to handle 3 different kinds of batteries, including wet and jell and AGMs, and charge rate can be adjusted from 2A to 40A, for lawnmower batts to deep cycle batteries or truck batteries.

The difference between (so-called) smart chargers and chargers w/o electronic processors is the modern smart chargers will monitor the battery, and will fall back to a monitoring maintenance mode. In maintenance mode, the charger will pulse the battery to maintain charge level, long-term. But, as/more important, the pulses are designed to keep sulfate from forming and hardening on the plates. (Although the Black and Decker unit will maintain a battery, it can be replaced with a BT (e.g., Junior) to take over the "watch duties", freeing up the big charger for other duties.

I have found that the Black and Decker unit I have for some reason will not charge a batter that has fully discharged. It throws a "code" indicating the battery is truly dead - beyond recovery. Not necessarily true...

I have an old "dumb" battery charger that puts out a charge current, regardless of whether there's a dead battery or a dead possum connected to it: it will produce a charging voltage/current! With that, after and hour or so, the Black and Decker will recongnize the battery as worthy of the effort to charge it, and then do so.

A word about sulfate process and cold weather:

A battery that is first fully charged will be not only be safe from freezing, but charging will disperse any noncrystalline sulfate and keep it from crystallizing (forming an insulating layer upon the plates - effectively reducing the area of the plates which can be used to generate current).

Cold also slows the sulfate process down significantly. In fact, a battery fully charged before being disconnected from service and put into cold storage - especially in a non-heated environment, can withstand long periods of storage, e.g., over winter months, with minimal ill effect.

I personally don't have any comparison examples of each method, i.e., using a maintainer vs. the full charge/cold storage. And, I imagine data with the cold storage method would be subject to the variables of the storage temperatures over the entire dormant period and the initial condition of the battery before being put in storage, etc. But, in my personal experience, here in the frozen north, the "minimum" life for batteries on the BTs is 7 years, and the longest is over 10 years and counting! For what it is worth, the new battery in my F150 truck lasted just over 3 years w/o being on any BT, nor being disconnected. It's a big bugger, and set me back over $156 @ Auto Zone. I think a maintainer is "in the works" now.