Good battery connections will significantly
improve the reliable performance of your battery. In contrast,
poor battery connections may suddenly cause your system to act as if
your battery was dead!
For example, this
terminal was connected in our test vehicle to a 5 year old battery in
poor but functional condition. We allowed the connection to
corrode. This battery started the vehicle just fine with no
problems. That is until one hot day during a sales trip.
The vehicle started and operated fine at the beginning of the
trip. But after the vehicle was warmed and the day became hot, we
observed the following symptoms:
We parked the vehicle and made a short visit with a
customer. When we returned and attempted to start the vehicle,
nothing happened; no lights, no cranking!
It was as if the battery was not there. We needed to be at
our next appointment and soon! Fortunately, our test
vehicle was equipped with a backup battery and and an early model BIC-75300A. We were able to
quickly switch "ON" the BIC to combine the batteries, start the
vehicle, and make the remaining appointments throughout the day.
After starting with the backup battery, we returned the "Remote Switch"
to the automatic position. But, with the AC on, and the vehicle
RPM reduced to idle, the engine suddenly died. We concluded that
the main battery had been electrically disconnected. So anytime
the vehicle load exceeded the alternator output, the system voltage
dropped below the minimum required to operate the engine.
Therefore, we operated with the "Remote Switch" in the ON position for
the remainder of the day.
When we returned, we
were able to closely analyze the failure mode. We observed that
the battery had leaked acid through the top seal (not the vents!) and
from the positive terminal. We observed battery acid all around
the battery and the battery tray was wet (with acid). The
corrosion on the clamp was so hardened that a special tool was needed
to keep the clamp from moving while the screw was broken loose.
After the clamp was removed, we took it to the lab for analysis.
As you can see in the photo, we observed a black layer on the lead as
well as the hardened yellowish crystels. Measured with an ohm
meter, the clamp showed no conductivity anywhere on the black
layer. This layer must be penetrated in order to achieve an
electrical connection. We determined that the leaking acid over
time and hot conditions caused this insulation layer to crystalize to
the point of breaking the electrical connection.
With this kind of problem, a simple jump start would not
have helped! Neither would a battery saver "disconnect"
device. The fact is, this battery was near full charge!
When we replaced the battery clamp, the battery performed as it always
1) If you use emergency
type of battery clamps, best conductivity is made if you solder the
wire after clamping.
2) Seal your cable wire exposure. For a clamp like
in the photo, use something like "Plasi Dip" from NAPA. If you
use a crimp type of clamp, then use a sealing type of heat shrink or
3) Avoid cheap batteries that are
prone to leakage.
4) Use corrosion inhibiting felt washers.
5) Ensure your alternator is regulated at the proper
voltage (14.0 to 14.7 volts depending on temperature.)
6) Use of a sealed AGM type of battery will reduce the
probability of corrosion problems.
7) Use Copper Wire!! We helped troubleshoot for a customer, who was very happy with our BIC-95150B for over 7 years, but found that his system suddenly stopped charging. It turned out that the BIC functioned just like new, but the charge wire had corroded through. It turned out that the stereo shop who did the install went the cheap route and used aluminum wire. The dissimilar metals caused the aluminum to corrode over time. So, just use Copper wire! Tin plating or gold or silver plating is fine, but the Base wire should be copper...