The life span of a battery can’t be judged just by the rating on the sticker. Thats just the period of a pro-rated warranty. The only way to determine if a battery is still good is to do a load test. With a battery charged to 12.6 volts, place a load of half the CCA rating on it for 15 seconds while monitoring the voltage. If it drops below 9.6v at any point of that 15 seconds it is junk. That is the absolute cutoff, no grey area. If 14 seconds into it you read 9.5v you toss it. You can destroy a near new battery by constantly running it dead. If you have to jump it all the time because your alternator is junk or a dome light stays on you do damage every time it is discharged. I’ve seen batteries only 6 months old get stone cold dead twice and were so sulfated inside they would never come back to full charge again. If you live in an area that gets cold out and allow a battery to completely die the specific gravity of the electrolyte drops and the fluid feezes, bulging out or rupturing the case and rendering your battery garbage. Also voids the warranty on them should the person you go to for an exchange have his eyes open and look.
On the flip side I’ve seen batteries outlive their useful life on rare occasions, I used to own a Jeep that had a 60 month battery in it that was 70 months old when I bought it. Never had a single issue, I never had to jump start it. I could go out and fire it up in subzero temps when it had sat for a month or two without fail. I sold that jeep when the battery was 8 years old at the time and still had no issues. It was the Rasputin of batteries and while not to be considered the norm can happen.
You get what you pay for. I have never seen good results with Wal-Mart batteries lasting. Bear in mind when comparing prices of the collateral damage that a bad battery causes. When a battery is not capable of charging properly it causes the alternator to work much harder than it should and fries it out early. With many reman alternators costing $180 and up, plus being in awful spots to get at, that extra $30 you pay for a quality battery is a good investment.
A wire brush battery post cleaner is what I’ve found to be the best thing to clean cables. The idea of baking soda and water or the various aerosal battery cleaners on the market is to neutralize any acid residue present on the outside of the battery. I recommend coating the connections liberally with dielectric grease when you reassemble them. A clean and inspect like crimsonavenger mentions doing every 6 months should suffice and will save headaches in the future for you. So many driveability and electrical issues can be traced back to poor battery connections its not even funny.
You asked when you should add water. If this is a sealed automotive battery like most are the answer is a very firm NEVER. It says in pictures and several languages to not touch those caps for any reason ever. If this is a tractor battery that still has screw on ports above each cell you add water as needed and test each cell with a hydrometer. I doubt you’ll be running into any of these unless you work on electric forklifts or some older 6v farm machinery.
I’ve never seen any evidence either way of the felt discs being any good, but they are cheap and worth a gamble if it makes you sleep better at night. If coated with dielectric grease they would take up airspace where corrosion could form so maybe they do help. They certainly won’t hurt anything nor will they bankrupt you. Use them if you wish.
Batteries used seasonally, such as ones for boats, ATV, motorcycle, riding lawnmower, etc. will benefit from being stored in a heated are for the off season and hooked up to a maintenance charger that will add small amounts of power when they need it to keep a full charge. They are recommended by all battery manufacturers. As I mentioned earlier, a full discharge or two will sulfate the battery and kill it early. An exception to this is a deep-cycle battery like you would use for the fish finder on your boat. They are made to be fully discharged over multiple cycles, but don’t deliver the very high cranking amps that a starting battery does. Still, its a good idea to keep it on a trickle charge and it will be ready when you need it. Before putting a battery on a maintainer charger, you must first get it up to a full state of charge. A maintainer does just that, maintains a full charge. It doesn’t change a dead or partially discharged battery for you.
As far as safety, remember batteries are heavy creatures. They are full of lead not feathers. Make sure you’re at a decent leverage point to lift it so you don’t throw out your back. Its amazing how easily even a strong man can rupture a disc at the right angle of lift, and you will never heal fully from that. I know, sounds like that same OSHA video you fell asleep watching your first day of work but know it can happen. If you’re going to blow out your balls do it on your girl not on your truck. OSHA idiots tell you to wear gloves, face shield, etc. I don’t and I doubt you do. What you use is your eyes and common sense. Look over the battery a bit. Is it wet? Look for leakage. If you see any you can neutralize it with baking soda and water or one of the various sprays available. You probably already have the soda in your kitchen. None of the sprays will work any better than that. After you get a leaking battery out, pour the baking soda/water mix over the tray for the battery until it no longer foams up, then rinse with water. Otherwise the acid will just eat away at your car. If you get some acid on your hands, dump some of that baking soda on it and rinse with water. If you get it on your clothes I’d get them off and in the soda soon or you’ll wake up tomorrow and see holes in your clothes on the laundry pile.
I would also advise you to be looking at the cables and ends that connect to the battery. If corrosion gets inside the cable insulation even a new battery won’t help. Its called Green Death. A voltage drop test will show it easily. I would NOT ever use the universal battery terminals where you chop off the old one, strip the wire and bolt a tab down to pinch the wires. They are asking for trouble and guaranteed to cause them. You can’t fit heavy traffic through a 1 lane road and you can’t deliver enough amperage with corroded cables or bad connections. They are just as important as a good battery. When a customer has a no-charge or a no-crank condition, I always do voltage drop tests on the cables before I will replace the starter or alternator because I’ve seen too many times where people have replaced the battery, starter, alternator for hundreds of dollars and all they really needed was the $20 cable I put in it.
Cbriden you have hit it on the head about batteries causing so many problems for you guys. I’m glad you asked about it and I hope I answered all your questions. Hopefully Eric puts out a vid on it this year when he gets back in the office. He’s a busy guy, hope he’s enjoyed some time off with the family. Happy New Year guys.