To be absolutely sure there is no danger of voltage spikes, ALWAYS disconnect the NEGATIVE
terminal first, followed by the POSITIVE terminal.
When reconnecting the battery, connect the POSITIVE terminal first,
followed by the NEGATIVE terminal.
Most car manuals always advise this anyway as best practice, but who ever takes much notice of that!
Following the incorrect procedure has cost at least one owner his AFT ignition box!



Always keep the terminals protected from moisture in the air by coating them with a
thin layer of petroleum jelly and if your car is in storage, regularly remove
the Tickford battery cover to check that there is no build-up of
condensation on the battery casing.
The battery in the photo above does not have its terminals protected and the sides are
 running with condensation that will drip down and eventually rust the battery tray!
And while we are on the subject of the battery tray, next time you have the cover off,
it is a good idea to quickly check the welds holding the tray in place.
 Brian has come across these fracturing and the tray becoming loose.
It would be a good idea to install a small charging lead at the same time
 (as shown in the photograph above) and invest in one of those
battery optimiser trickle chargers that are designed to keep
the battery healthy while your car is stored.


Adrian uses this model to keep his battery ready for action


As general safety points:
Always disconnect the battery before working on a car just to make sure
there is no danger of short-circuits.
Make sure the disconnected battery leads cannot fall back and touch
the terminals by accident.
NEVER rest anything metal like the spanner you have just used
on the top of the battery in case it creates a short.