Swarthy got a new battery last night.
I did not replace it with the standard starting battery, but rather a group 24 deep cycle battery. These are also called marine batteries (but not dual purpose). They are designed to be discharged and recharged where a starting battery isn't. They will die a quick death if you deeply discharge and recharge them. However, the deep cycle does not provide as many cranking amps as a starting battery. I've used deep cycle batteries on several cars and starting has never been an issue.
Why might you want to do this? It is possible a deep cycle battery may be a bit cheaper than a starting battery. Or, you may be installing a beefy audio / entertainment system and need some additional reserve capacity. Or, you may run a 110V power inverter off your battery and would like some more run time on it. In my case, I plan to disable my alternator eventually. This reduces an accessory load on the engine. This does two things for us. First, it frees up some power that the alternator would otherwise be consuming. And, by freeing up that power, it also means I'll get better fuel economy since I'm not having to use power to recharge the battery.
You might say "But Daox, your battery needs to be recharged." I agree, and I plan on adding an onboard battery charger and plug in when I am home. This essentially makes my Mirage a mini plugin hybrid! However, that mod info is for another day when I get to it. This is simply the first step toward that. So, lets get back to the battery mod.
The new battery is slightly larger than the OE battery. Its just about the same height (a little taller), the same width, and a bit longer by an inch or so.
It fits into the car pretty nice. It is at the extreme of having enough threads on the hold down brackets, but it does work. However, there is a problem where it won't just drop in. The positive and negative terminals are on opposite sides as the OEM battery. There is no way the OEM post connectors have enough slack to make things work, so I had to get some parts to make things work. I got some extension cables. One end of the cable has a female automotive post connector and the other has a flat connector with a hole in it. So, with the flat connector I got a male automotive post with a bolt through it so they can bolt together effectively making an extension cable.
With the extension cables put together, I was able to install the battery in the car and even hook it up properly. I used a couple zip ties to keep it somewhat tidy. I'll probably clean it up a bit more when its not hovering near 0F outside.