Does a battery "age" from non-use

[ard]

I have a $15 off coupon at Wheel Works and thought about buying a new Interstate battery for my 993. The current battery, also an Interstate, is getting a little long in the tooth but tests fine and doesn't leak.

During the non-driving season, I do NOT keep the battery constantly charged via a trickle charger, but I do plug it into the charger a day or two before I plan to take the car out. Don't know whether this adversely affects the life of the battery - the 993 has enough electronics which operate, at least intermittently when the car is off, that there is a small current draw.

Question: is it penny-wise and pound-foolish to buy a new battery @ a $15 savings now and have it sit around at home until I need it or is there no harm to storing a new battery for an extended period of time without loss of performance.

Inputs much appreciated

[r_towle]

When a lead acid battery is fully or partially discharged, lead sulphate forms at the electrodes. If the battery is allowed to remain for a prolonged period in a discharged state or with a very low state of charge the lead sulphate may form into large crystals which are very difficult to convert back into lead and sulphuric acid by the charging process. The formation of these crystals is called sulphation and causes a permanent loss of capacity of the battery. To avoid this problem lead acid batteries should therefore only be stored in a fully charged condition and the charge should be topped up from time to time during storage to compensate for the self discharge of the cells.

To prolong shelf life without charging, the batteries should be stored at 10°C or less but the electrolyte should not be allowed to freeze. When the battery is fully charged the electrolyte is sulphuric acid solution and the freezing point is -36°C but it rises to 0°C in the fully discharged state when the electrolyte is simply water.

[r_towle]

Calendar Life and Cycle Life
Battery performance deteriorates over time whether the battery is used or not. This is known as "calendar fade". Performance allso deteriorates with usage and this is known as "cycle fade"


Battery Shelf Life like calendar life is the time an inactive battery can be stored before it becomes unusable, usually considered as having only 80% of its initial capacity.

[Evans, Marv]

Is there any way to test the remaining capacity on a battery?

[javadog]

You can test the voltage, or the specific gravity of the electrolyte.

JR

[Quickstep192]

great treatise from r_towle on what happens to a stored battery when not in use. I wish I had been on this forum and consulted r_towle's expertise before I got to learn about sulphation the hard way. Since ard is looking to buy a new battery and store it until he's ready to use it, can he avoid sulphation if he can get the battery without the acid and add the acid later when he's ready to use it? A while back when I ordered Porsche batteries, they shipped dry. I've since switched to AGM batteries which appear to eliminate all of these problems.

[kodioneill]

A load test would give you an accurate profile of the battery strength.

The voltage of a battery being charged should not exceed approx 13.9-14.0 volts if it does it usually indicates the plates are sulfated. You can use the load test to see how the battery stands up to a draw.

[wayner]

Another tidbit:

The main difference between a typical battery and an RV deep cycle battery, is that it has more space below the plates for sulphate to fall without shorting the plates. A chunk falling off and shorting two plates is what kills many normal batteries all of the sudden.

[DanielDudley]

Seems like a battery tender would be a better investment.

[cgarr]

too bad you cant get it without electrolyte and add it when your ready then it would last forever:

[Rusty Heap]

These PULSE chargers, inject a high frequency AC signal into the battery as a trickle 2.5 amp charger, but the main benifit is battery plate cleaner of sulfides.

pretty cool stuff, military application that is now making it into the civilian market. Gotta buy one of these, about $69-89 on Amazon or Ebay.

XtremeChargers.com | Renew-It Pulse Technology

[RSBob]

I am no scientist nor do I play one on TV, but over the winter I bring into the house my lead acids (riding mower, 914) AND keep trickle chargers on them. I also keep a trickle charger on my deep cycle dry cell on the 911 at all times since there is a tiny draw which will kill it after a month of no driving. Probably overkill but never had a problem. Bought 4 Battery Buttlers trickles for cheap cheap (recommended by the local PCA tech-head) and they are great for the price. BATTERY BUTLER - Battery Float Chargers (6 & 12 volt) & Battery Quick Disconnects - www.batterybutler.com

[ard]

great comments and good insights and thank you for those, but I am still none the wiser regarding my original question. No big deal, $15 saved or not fortunately isn't a life-changing event.

What I hear is basically "don't buy it and store it since you can't get it dry because it will age chemically just sitting there".

[DaveHak]

I just bought an energizer trickle charger, it had good reviews.

[wwest]

Originally Posted by Evans, Marv

Is there any way to test the remaining capacity on a battery?

Well, yes, and NO..

You can test the capacity of the battery structure itself but you cannot detect how soon the "pile" of material flaked, flaking, off the plates and laying at the bottom of the battery case will rise to the level to begin shorting out individual cells.

[wwest]

Originally Posted by ard

great comments and good insights and thank you for those, but I am still none the wiser regarding my original question. No big deal, $15 saved or not fortunately isn't a life-changing event.

What I hear is basically "don't buy it and store it since you can't get it dry because it will age chemically just sitting there".

Easy answer....

buy the new battery.......but put it to use and store the used battery.

In 3-5 years or so, if you remember you have a spare battery stored somewhere, you can trickle charge it within 2-3 days and have a temporary "spare".