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Electrical: Engine Starting, Charging
Car Battery Replacement Tips.
Purchasing Tips:
Sourcing US Batteries. [Consumer Reports] Most auto batteries are made by just
three manufacturers: Delphi, Exide, and Johnson Controls Industries. Each makes
batteries sold under several different brand names. Delphi makes ACDelco and
some EverStart (Wal-Mart) models. Exide makes Champion, Exide, Napa, and some
EverStart batteries. Johnson Controls makes Diehard (Sears), Duralast (AutoZone),
Interstate, Kirkland (Costco), Motorcraft (Ford), and some EverStarts.
[Tips from Rich:] Being involved in the telecommunications power business since
Mr. Bell was a pup, I have some knowledge about batteries. If there were any
additives that are useful in the long term they would be commonly used. There are
not. As to size, buy the biggest heaviest battery that will fit. Typical car batteries
are around 50 amp hours and weigh around 45 pounds. Some parts chain may sell
you a cheap, light battery with a warranty, but they are counting on you not
owning the battery when it goes bad. Since batteries do not like to be used a small
battery is stressed more when cranking and when charging. Sure, a low charging
rate is best for a battery, but you have no control over that. At some speed your
alternator puts out 70-100 amps. Deducting 20 amps for fuel pumps and ignition
the rest is going into the battery.
Car batteries are designed for high-rate discharge (cranking) and a reasonable life
of 5 years. Other designs optimize other types of service. Marine Deep Cycle
batteries accept repeated full discharge conditions. Telcom batteries are designed
to sit there for 10-20 years with charging voltage applied and ready for the very
infrequent discharge when AC power fails. UPS batteries are similar but due to the
competitive consumer market they will not last very long.
Design considerations include a space at the bottom of the case so that material
that falls off the plates can accumulate. Eventually it piles up enough to short out
the plates. Longer life batteries have more space but they also have less lead and
therefore less Amp-Hour capacity in a given size. The 20 year batteries have a lot
of extra space added for a long life seal where the post comes out of the case. It is
the nature of a battery to eat away the post seal. When it does you get the white
powder. Felt washers and grease do not keep the acid from eating the seal away.
The white stuff is the end result of the seal failing and efforts to remove the white
powder do not cure the problem.
It is useful to remember that there is no magic in batteries. Every manufacturer
understands the chemistry perfectly. The only difference is in the PR and
advertisment depts. The biggest battery you can fit has a chance of having more
space below the plates and a better seal. When Johnson Controls made the Die
Hard batteries they were good. Now that someone else makes them they are not
so good. Since Interstate distributes J. C. batteries that is what I buy. You will not
hurt the alternator with a bigger battery. I always had good luck with OEM Volvo
batteries but I understand that the 850s had a battery vith frequent failures.
Sounds like the Purchasing Dept saved the company a buck or two but gave the
reliable cars a bad name. This is not the first time that has happened, and will not
be the last.
file:///C|/Users/Steve/Documents/Volvo%20FAQ%20Updated/ElectricalStarting.html[01/13/14 10:02:47 PM]
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