Well there’s strong debate, even between full time mechanics, whether to disconnect the postive or negative battery cable.
I haven’t really taken a side because it seems there’s avdvantages to disconnecting either!
I don’t know any mechanic that doesn’t follow this rule of thumb.. The negative cable should always be removed first and reconnected last.
My guess is you are not the one and only reader of the link I sent you, so here it is again with a few others… I thought I explained the basics of it in my las post about it… lol
That is 5 different sources on how/what to do when disconnecting/connecting…
I can post more if you would like… 
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I’m talking about for long-term storage.
Whoever removed whichever cable when I was gone for 6 months because the horn/alarm started blowinging by itself randomly only loosened the kreldan thing, but left it on the terminal post. When I came home, the battery was completely drained and I needed to have AAA come and jump it.
So I’ll ask again: in a future such scenario, long-term storage, not a jump-start, but for future long-term storage, which cable should I remove?
The answer stays the same, unhook the negative 1st and hook back up last…
Once the circuit is broken the circuit is broken, the only thing you can/might have from there is a surface discharge…
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Thanks.
And for my purposes, only the one cable(negative)?
I should have picked up on that based on the fact that on 2008-12 Accords, there is no slack around the positive cable. Negative cable? Enough slack to stow it decently far away from that post.
I’m admittedly as ignorant a member of the general public about which battery cable to remove for any purpose, as I am knowledgeable about tire pressures!
Your welcome sir..
Neg removed will be fine as far as the vehicles electrical system goes, but for long term you might disconnect both (still neg 1st) to keep corrosion down on the remaining (pos) cable terminal, or just clean the battery, terminals and post really good with very hot water (w/ baking soda) and then apply a thin coating of dielectric grease to the terminals… Works great in my area anyway…
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I don’t really see the advantage of removing the battery cables on a modern car during storage. The battery has internal resistance and will self-discharge over time even if disconnected. It has to be periodically re-charged regardless. Disconnecting it just extends the interval a bit. In a properly functioning car, the keep alive drain should not be so high as to warrant removing the battery and in many cases, the side effects of removing power may be more onerous than the slightly more frequent charging interval (e.g. entering security codes, battery status that may require factory tool, certain presets etc).
I have a schedule on my calendar during winter months to re-charge batteries in stored vehicles/boats etc. so I don’t forget.
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I am an electrical èngineer. Disconnecting either terminal breaks the electrical circuit and the PCU has to recalibrate when you start driving again. Disconnecting the ground terminal is a little safer JIC someone carelessly drops a tool on the battery and shorts the positive terminal to the car. When removing a battery disconnect the ground terminal first. When installing a battery connect the ground terminal last.
The battery will last longer if it is kept fully charged and not overcharged.
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Back to the OP, having owned several Brit cars, the problem wasn’t Lucas’ design or manufacture but the car manufacture’s lack of understanding of the benefit of waterproofing. Coming from a country where rain and mist is a fact of life the car manufacturers seemed to go out of their way to ensure that rain would be channeled from the roof to the dashboard and practically every electrical connection would be placed in a location to encourage maximum corrosion.
OTOH, if you want to see really terrible electrics consider the Italian cars of that era which included inadequate wiring, inadequate components, sloppy assembly and fuse boxes that would melt down and burn out. 
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Yup!
One of the indy foreign car specialists who I used in order to keep my Volvo running used to complain about the electrical systems on the Fiats that were brought to his shop.
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In high school I’d deliver chicken in a fiat. That was the first and last Italian car I ever drove. I think the boss got it from the junk yard down the street.
Why would he complain? Fiats were his bread and butter.
I worked with some thermal engineers with that attitude. The mission systems engineer always had more questions after they answered the previous ones. Our lead engineer told them to keep quiet because the mission systems engineer kept them in business.
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I guess that I should have explained this situation much better. Almost all of my visits to his shop were for my Volvo’s myriad electrical problems. On at least one occasion, after I explained the latest electrical issue to him, he said something along the lines of…
If you think that the electrical systems on Volvos are bad, you should be very glad that you don’t drive a Fiat, because they’re much worse.
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I’ve heard that meme countless times too, but my own experience hasn’t been nearly that bad either. Most of the issues I’ve had with older British cars were mechanical or rust-related, not electrical. I think a lot of the Lucas reputation comes from jokes being repeated more than real-world failures.
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