Battery Freshness Questions

[Touring5]

I had to replace the battery in my 528i yesterday, opting to get the Duralast DL49 model. I knew it is recommended to try and get the freshest battery you can, so I made a point to look at the stickers on the batteries in stock. The one I bought had a sticker that said "10/07", so it was about 3 months old - should be good.

Then I got to wondering. Since some battery size/groups are less common that others, wouldn't they be in lower demand and thus not sell as frequently? If so, then I'd figure those batteries would be prone to sitting longer on the shelf. So what happens to these "stale" batteries? Retailers say they rotate stock to maintain freshness. Just curious what happens with the older units. Do they send them back and recycle them, have a way to "freshen" them up, or do they slap on a newer sticker and put them back on the shelf?

In one thread someone said that Interstate sells them as "econo" units. I noticed that AZ has a "value" line, perhaps that's the old Duralasts.

 

[Eddie]

I don't think they send them back for sure. They just sell them and if the battery lasts through the initial warranty 12-18 months it is good enough. They then pro-rate after the initial exchange warranty so you can't really win. CU used to have and publish the date codes but, I've forgot when they did this. I just do as you did and you should be good to go.

 

[Jonny Z]

I think they recharge them, and slap the sticker on it for the last time is was charged. As long as the battery is periodically recharged, it should be fine. It does not age well when it not fully (or closed to) charged.

 

[Hootbro]

Originally Posted By: Touring5
..... I noticed that AZ has a "value" line, perhaps that's the old Duralasts.


They are not "old" Duralasts. They are built to a lower quality price point and hence the lesser warranty. I just bought a Valucraft for my Cavalier two weeks ago and it was fresh with a 12/07 build sticker on it.

The build date sticker stays static with the unit and is not "updated" when and if they top charge it periodically.

 

[brianl703]

I've seen year-old batteries at Costco lately. At some point they're going to have to realize that nobody is going to buy that battery.

 

[White 03]

I just bought some Costco batteries for myself. The sticker that was on top of one of the ones I bought was for next month. Two others were the same month. The date codes which were stamped into the batteries in an inconspicuous spot and needed a code to decipher, were about 7 months old.

I asked if the sticker was the sell by date but the sales guy had no usefull information; lots of wrong answers but no information. He even said 3 years was the longest they keep them then said they would store even longer. Of course they could never be charged up because of the plastic caps on the posts.

Even so I thought I would try them.

 

[brianl703]

From what I've seen the sticker is the month it was manufactured. I've never seen one for next month.

 

[White 03]

I bought the Costco battery on 27Dec07, a couple of weeks ago and it has a little round sticker, about an inch around, that says 1/08. The little sticker is something anyone could remove and restick on another battery, I suppose. It was probably put on by the local costco, but I really don't know who put it on. I am pretty sure if I brought the battery back in they would use the date code hot stamped into the case and not this little sticker.

To read the date code I used information from this web site:
http://jgdarden.com/batteryfaq/carfaq7.htm#freshness

This date code is hard to find and hard to figue out probably something they don't want the public to pay too much attention to.

Only thing I can figue is the little sticker is the sell by date, although the sales guy said no. But, I don't think I would believe anything he would say.

 

[brianl703]

I don't think the sticker is the sell-by date because, for example, batteries that say 11/07 on them only started showing up at the local Costco in December.

It could be the date that the battery is supposed to be put on the shelf for sale.

 

[White 03]

That is a possibility.

I wasn't looking at very many batteries just the ones for my Accord and Ford PU. All the Accord ones were 1/08 and all the Ford ones were 12/07, this was at the end of December. They probably had 4 to 8 of each.

 

[Carmudgeon]

At my Autozone, batteries carrying the 12/07 sticker replaced the 11/07 batteries about midway through December.

If you don't trust the stickers, the date codes are still stamped onto the cases. My battery coded for 11/07 has a 11/07 sticker.

I wouldn't buy a Costco battery unless I knew what I was getting. In the warehouses around here, fewer and fewer seem to be even stocking car batteries, and the one that had them had some pretty old stock mixed in with the new.

 

[brianl703]

You can also use a multimeter to check the battery voltage before you buy it. They start at about 12.6 volts and drop from there as they sit, unless they've been recharged. I don't think I'd buy a battery that reads below about 12.5 volts.

 

[Hootbro]

Originally Posted By: brianl703
You can also use a multimeter to check the battery voltage before you buy it. They start at about 12.6 volts and drop from there as they sit, unless they've been recharged. I don't think I'd buy a battery that reads below about 12.5 volts.


Voltage is not always a good indicator of the battery. Many batteries can fail under amperage load and then return to proper voltage once the load is removed.

 

[brianl703]

It's a good determination of how long a battery has been sitting without being charged. State-of-charge is directly related to the open-terminal battery voltage. If the open-terminal battery voltage is high enough then and only then do you do a load test. (Doing a load test on a non fully charged battery is a waste of time and will produce misleading results).

 

[NYEngineer]

Those little date codes are the build dates. My best friend has a battery store. Once, we were in Wal Mart or Costco and just for laughs were reading the dates on some batteries on the shelf and found one that was almost two years old.