After experiencing a dead battery after winter storage, I decided to invest in a battery disconnect switch for my engine starter battery. The Chevy van uses a side post battery. A quick Google search for a side post battery disconnect switch turned up several. The one I used is made by Gamma Electronics. You can probably also find this locally at automotive stores. This is a very simple device. Two overlapping metal plates are separated by a foam insulator. A screw with knob head is insulated from the top plate, except for the flat head of the screw. This screws into the bottom plate where it is in electrical contact. When it's screwed all the way in, the head makes contact with the top plate and completes the circuit. If you unscrew it a few turns, the head no longer makes contact and the circuit is broken. Very simple, very easy. Actually quite ingenious.
This installs onto the negative battery side post of the engine starter battery. The existing cables that are screwed into the battery post are disconnected from the battery and connected onto the bottom hole of the disconnect switch, which is threaded. You need to use the supplied washer to get this connection tight. The top hole of the disconnect switch is then screwed into the battery post using the supplied screw. Now it's really simple to electrically disconnect the starter battery for storage. Just a few turns of the knob and it's done.
Overview of battery with disconnect on negative side post terminal
Close-up showing disconnect switch. Just loosen the knob a few turns to disconnect.
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