I have a battery that’s needs replacing but decided I would use the battery from my second car and put it inside because I’m thinking of selling it as is and just wanted to do some diagnostic work.

I know I should be replacing the battery but like I’m said I’m near done with spending on this rust bucket.

Anyway as I tried to use my other battery it was too large to fit and the cables from bad car were too short. By turning the battery upside down though I think I could make the connection.

  1. At this point I stated to wonder if I could damage good battery so I stopped. So would turning it upside down damage it or having it lying diagonal at 45 degrees?

  2. On the other hand since the cables were too short if I just used spanner’s to bridge the gap from the terminals to the batteries would this have worked I.e. can I use spammers to conduct electricity to the battery by mere contact?

  3. Are there cables or something else I could use to extend reach if so must they be if a certain specification?


  • 1
    Is this a wet cell battery or AGM? Sep 20, 2020 at 19:14
  • @PAULSTER2 hmm I’m not sure. Car is civic coupe vti 1999. A’s I moved it around I could here liquid/water splashing in it so I imagine it is wet? Sep 20, 2020 at 19:28
  • 2
    never tip a lead acid battery or you will spill acid and injure yourself and damage your car. Sep 21, 2020 at 8:43
  • As much as I appreciate the valuable comments above and answers below, I have an alternate opinion. If you are flipping the battery over to touch the terminals to those of another battery for the purpose of starting the vehicle, it is relatively safe and effective provided it's a sealed lead-acid battery. If it's a gel or AGM battery, even better. If it's not sealed, it'll leak and melt your flesh. I wouldn't recommend leaving it that way for an extended period, but it does work if you don't have an alternate solution. My biggest fear would be accidentally connecting the wrong terminals. Sep 21, 2020 at 18:22

2 Answers 2


As very few cars of that age used gel batteries and yours is most likely a lead / acid battery putting it on its side or upside down will cause acid to leak out.

Not a good idea as it corrodes or damages most things.

As for the idea of using spanners to make connections between batteries, that is such a poor idea - they can get hot, in fact hot enough to glow red under certain conditions but you will have left go well before then. Not only that but the chance of a spark is very high and that can ignite the gases given off by a battery which can easily explode. And yes I have seen batteries explode.


Never tip of invert a lead acid battery, it could lead to acid spilling as others have said.

As for your second point, No. Just no. By which I mean no, nie, nyet, nein, non, no. That's nearly as dangerous as jacking up the car and attempting to support it with a sponge.

If you must really connect a battery that doesn't fit, use proper certified jump leads. Car batteries hold a lot of charge, and can release it very quickly - current is more dangerous than voltage, and certainly more likely to start a fire.

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