battery charger for 328

Any grounded metal you can find AWAY from the battery.

The reason you don't want to attach the neg. cable to the neg. terminal on the battery, is because gasses emitted from the battery are explosive.

Connecting both cables to the battery can create a spark at the terminal, igniting the gasses.

Connect the neg. cable as far away from the battery as possible.

 

If it's a "battery tender" which senses when it needs to be on or off based on your battery's voltage, then the easiest way to use it is to rewire the ends into a cigarette lighter adapter from Radio Shack or elsewhere, and plug it in there. That way you don't have to pull the spare tire to get to the battery every time you want to keep it on the trickle charger.

 

Also be aware of painted or undersealed surfaces. You want a good connection to grounded bare-metal, such as a nice bolt-head off the chassis.

 

On a related note, what do people do about trickle chargers and closed garages?

One of the reasons I don't charge as much as I should over the winter is that I don't like to leave the garage door open, and I always open the garage door when out-gassing hydrogen from the battery (charging). Does anyone worry that they're putting hydrogen (think "Hindenberg") into a closed garage when using a trickle charger?

An Optima is a sealed battery, but with the one that I bought in September being dead already, I'm thinking maybe an Interstate with a vent connection, routed to outside?

Or am I worried about nothing? (Or not much?)

 

FWIW, here's mine. I think you are better off charging through the 12v cig. lighter outlet. It's "plug and play." (Scroll down and you'll see some pics).

http://www.ferrarichat.com/forum/showthread.php?t=22892&page=2&pp=20&highlight=328+battery

Ron

 

Modern lead-acid batteries have a catalyst in them to recover the hydrogen from normal charging operation (otherwise you'd periodicly have to add water). Optima batteries are even better at recovering it.

Hydrogen isn't really an issue unless you're charging at a pretty high rate such as jump starting or a high (50+ amp) rate that generates H2 faster than the catalyst can recover it.

The other thing that can generate H2 is over-charging, as the battery can't store more energy so it has to go somewhere. Again the catalyst can handle a moderate over-charge rate, more than a trickle charger puts out.

Also H2 rises very quickly & thus will dissipate.

I don't worry with a trickle charger, or even my 15A charger. I do keep the charger unplugged while attaching it to/removing it from battery terminals to err on the side of caution.

Certainly a trickle charger is well within the battery's self-recovery capabilities.

However, the general public can't be expected to know enough to know whether they likely to be dealing with H2, or not. Nor can they be expected to remember more than 1 rule, so they're just given the most conservative rule. Taught it to my sons as well.

 

Many chargers don't have much separation between the battery leads. But if you check, that dual cord that ends in the battery clamps may be "zip cord" -- a slight pull will separate the two wires, letting you get some distance between them.

If you hook the plus lead to the battery itself, you'll need to have some separation to find a good chassis ground. You might see if you can find the hot lead at the starter, in the back. There are lots of grounds in the engine bay, and the starter wire is certainly thick enough to handle the charging current.

But, as was said above, for a "keep it fresh" trickle charger, it's lots easier to connect to the cigarette lighter.

If you want to keep it out of the interior, you could get a connector pair at an auto parts store, wire the female side to the battery connectors, and the male side to the charger. If you mount the car side somewhere handy (such as under the front bumper) you can then connect your charger without having to remove the spare (and all the other junk you keep in the front bay ). Or you could wire your charger connector to the starter clamp and ground, and mount it in the engine bay.

Finding a metal ground under the front lid is a challenge. You might look around the headlight or windshield wiper. Or, if removing panels doesn't bother you, pull the fiberglass half shell and hook to metal around the brake or clutch pivot boxes.

I tend to disconnect the battery when charging, but for a trickle charger, I'd go with the cigarette lighter. That way, you don't forget to unplug before you drive off.

 

John,
I understand your dilemma. There is metal cross members you may be able to reach through the battery opening that may work....but, the bottom line, is it may be easier to just attach directly to the battery itself. Just make sure the charger is unplugged before attaching or removing the cables. This should prevent any possible sparking.

The other thing you may be realizing, is that a "standard type" battery charger is probably not the most convenient way to maintain your battery. The best way is to purchase a battery tender. Griot's sells those too, but you can get a comparable one elsewhere for less (even though I am a HUGE Griot's fan for most of his other products). Such as here: http://snipurl.com/7cod

You can then splice on a cigarette lighter plug adapter for easy hook ups:
http://snipurl.com/5rl7

Regards,
Dave

 

John,

I second (actually, fourth) davehanda, Ron 328, and mcharness in their recommendation to use a battery tender and to plug it into the lighter socket. No fuss, no muss. I got a Deltran from www.BatteryMart.com for $30 for the tender and $6 for the cigarette lighter plug. They also sell a 25' extension for the lighter plug lead for $9.

One caution: Plugging into the lighter socket after plugging the the tender into "the wall" might cause a blown fuse in the car. Maybe it's just my particular 328. It's best to plug into the lighter socket first, then plug the tender into "the wall."

Cheers, Mark

 

Haven't had that problem with my 308QV. I always leave the tender plugged into the wall and just remove and replace the car end. I think in 5 years of doing it this way, only once did I blow the fuse, and it was the one built in to the cigarette lighter plug end.

 

The braided cable to the battery disconnect is a fairly easy access ground point under the hood. Also, you know it's a good connection.

Never had a problem with blowing a fuse when plugging a batt. tender into the lighter socket. Only way I can see that happening is if the tender has a VY large internall electrolytic capacitor across it's output terminals.

Easy to blow the tender's fuse if you tilt the male cig. connector a bit when inserting & the center manages to touch one of the socket's side walls.

 

Anyone know a source for the connector that goes with the stock trouble light?

My US 328 didn't come (used) with the trouble light, but it's got the socket under the dash.

That might be a good place to connect a battery tender. That way, you don't need to find a place to keep the lighter when the tender is plugged in.

(Given that I don't have a factory trouble light, maybe it'd just be easier to repace the car side connector, too. Or just hook in a parallel connector.)

 

Got ya covered: http://www.rallylights.com/hella/cigar_plug.asp

You want the "BMW" plug....

Here's another (more expensive) source, that has pictures:
http://www.cyclegadgets.com/Products/product.asp?Item=PLUG

 

BTW, if you want to get a trouble light, there are various sources for them...they sell for around $50 with the cheap black vinyl case.