WTF? Replacing CPS2 suicide battery with regular AA?

Tech Talk
1

Update: So, I dropped off my non-modified ST board to someone to solder for me (my joint’s only hold for a couple days. anyone who says anyone can learn to solder by themselves is a liar. I need someone to teach me)

Anyway, So I decided to pop open the board that I thought had a keystone mod (i only had a quick look last time) and I noticed… WTF? it’s not a regular keystone mod. The battery older is actually on the DAUGHTER board. with wires leading to where the original joints were on the suicide battery. Ok. that makes sense… Since there IS room on the daughter board to hold a battery. but the WTF moment came when I looked at the battery:

It’s a regular AA? I don’t know much about battery voltages and amperages. and google isn’t exactly friendly recognising 1/2AA and AA together in a search and parsing it how I want it to.

Does it work out? Can I just stick in an Energizer AA into this? If so, why is the keystone mod a use the original 1/2 AA size? and not a regular AA size battery which is much more readily available?
Will it still last approximately 5 years? (I noticed tape across the battery with a date, and it was 5/2012)

I’m going tp run upstairs and take a photo with my nexus 7 right now and upload here…

Is that a regular AA battery? for comparison, I have an AA above it, and 1/2 AA with axial lead beside.

**TL; DR So I can stick in a regular energizer/duracell AA in there right? If so, is there any particular disadvantage to using AAs rather than the 1/2AA? Will the battery still last approx 5 years? **

Previous Thread title: cutting axial leads off suicide battery for keystone mod?

I have 2 st boards. I wanted to replace both suicide batteries together so I can keep track of the dates easily. I bought 2 suicide batteries and they arrived today. I decided to open the “newer” ST board first. Problem. There is what appears to be a keystone mod in this board minus the top cover (which wasn’t mentioned in the eBay description when I bought it.). The other board I have is normal.

So now I have 2 batteries with axial leads. I’m thinking about just cutting the leads off one of them and popping the battery in the board. Seems pretty straightforward. Might there be any unforseen complications with doing this? Should I just purchase the battery again without the leads?

2

As long as the battery still has the raised end so it makes contact with the holder, I don’t see an issue. Just make sure you sand it down so you are getting full contact with the base/raised bit rather than the stump of the axial lead

3

So, I dropped off my non-modified ST board to someone to solder for me (my joint’s only hold for a couple days. anyone who says anyone can learn to solder by themselves is a liar. I need someone to teach me)

Anyway, So I decided to pop open the board that I thought had a keystone mod (i only had a quick look last time) and I noticed… WTF? it’s not a regular keystone mod. The battery older is actually on the DAUGHTER board. with wires leading to where the original joints were on the suicide battery. Ok. that makes sense… Since there IS room on the daughter board to hold a battery. but the WTF moment came when I looked at the battery:

It’s a regular AA? I don’t know much about battery voltages and amperages. and google isn’t exactly friendly recognising 1/2AA and AA together in a search and parsing it how I want it to.

Does it work out? Can I just stick in an Energizer AA into this? If so, why is the keystone mod use the original 1/2 AA size? and not a regular AA which is much more readily available?
Will it still last approximately 5 years? (I noticed tape across the battery with a date, and it was 5/2012)

I’m going tp run upstairs and take a photo with my nexus 7 right now and upload here…

Is that a regular AA battery? for comparison, I have an AA above it, and 1/2 AA with axial lead beside.

Edited the First post too…

edit: Just found this: http://www.neo-geo.com/forums/showthread.php?22035-CPS2-suicide-question it basically answers my question. and says it brings it to approx 8 years instead of 5. But I’d still prefer confirmation from someone here. Simply because whenever I bump in to neo-geo tech threads it’s because i’m specifically googling for something so I don’t trust that community as much as here. (where I always come by and help people out, and interact a lot more, and know the general level of expertise and forum environment/culture)

I’d also prefer a more indepth answer with explanation rather than just “yes, you can do it and it will extend the life”. With doesn’t exactly give me confidence since it doesn’t provide any technical details i can confirm. (and it seemed like an off-hand comment too)

and If everything checks out, is there a particular disadvantage to using AA rather than 1/2AA? (basically to answer my question earlier, why does the keystone tutorial suggest 1/2 AA keystone mod instead of AA which is much more readily available?)

TL; DR So I can stick in a regular energizer/duracell AA in there right? If so, is there any particular disadvantage to using AAs rather than the 1/2AA? Will the battery still last approx 5 years?

4

As far as my quick re(google)search could tell me, the battery needs to be 3.6V and that the objective/requirement is that you need to keep the voltage from dropping below 2V to keep your decryption keys safe.

That panasonic you’re holding in your picture is a 1.5V and will not work. Put that in and bye-bye keys.

The battery that is in place is most likely an AA sized 3.6V Lithium battery, and the battery should last longer than a 1/2 AA though I would recommend changing the battery at 5 years just to stay safe. The biggest advantage is that with the holder it is easy to swap. Just remember, 3.6V lithium, not 1.5V alkaline.

5

That actually helps a lot. Yeah, the battery was just popped out of a television remote for comparison. Good thing that I did that and you noticed. Its partly why I had that wtf moment. Makes sense now since there are those lithium batteries now a days for energy hungry portable electronics. I said before that I didn’t know battery voltages, I assumed they would be a single standard across the same size. I DID know that a b-board needs 3.6v and recalled AAs being lower than. That thus the wtf moment. Now everything’s cleared up though. Thank you very much!

6

Also of note are 2 other things:

  • As mentioned by John_Smith in that Neo Geo thread, “…be careful to take note of the date on the new battery also. As in if it was made 2 years ago then it’s likely to mean 2 years off it’s life span.” Just because the battery is “new” to you, does not guarantee it hasn’t been sitting around some warehouse for some time losing life (yes, batteries lose life just sitting there, if you didn’t know).

  • Learn about batteries. What is an ampere-hour? If you don’t know the answer, you may be buying a battery that doesn’t last as long as you think it will. If a battery is rated for 1 ampere-hour (or more likely labeled “1000mAh” for 1000 milli-ampere-hours), what that means is that if you were running something off that battery that was drawing 1 ampere of current (1A), it would only last 1 hour. Thankfully, most battery powered consumer electronics don’t draw nearly that much current, and therefore last longer than an hour. All that to say, you can buy 1/2 AA 3.6V Lithium Ion batteries with different ampere-hour ratings which will have different life spans based on that rating. A typical rating for those batteries is 1200mAh, but I think I’ve seen as low as 700mAh. That’s about a 40% difference in life!
    -ud

7

Its a 18650 lithium ion cell. 3.7 volts and averages around 2500mAh.

Or least it looks like it. Prob a slightly diff version since 18650 cells are longer then AA.

8

Yeah I started looking at batteries this morning and think I found the right one. as well as did a bunch of googling on batteries and how internal resistance, voltage and maH affect them

9

Alright, I just picked up a battery, It’s essentially this except another brand
http://www.amazon.ca/Saft-LS-14500-3-6V-Lithium-Battery/dp/B002GK406C

I couldn’t find anything on the battery that’s obviously a date but I see a code

14 134 A 193

I’m assuming 14 134 is 134th day or 2014 ? so it was manufactured in may ish? I tried googling but couldn’t find anything specific.

the brand is “ultralast” though. if anyone has experience with that brand.