Solderless Battery Replacement
                            For NES Cartridges
                                   V. 1

                            By:  DarkBubble

                        (dbfaqs at gmail dot com)


Table of Contents

1.)  Introduction
2.)  Disclaimer
3.)  What You Need
     3a.)  Tools
     3b.)  Material
4.)  Preparing the Patient
5.)  The Operation
     5a.)  How it SHOULD be done.
     5b.)  How I did it.
6.)  IT'S ALIVE!
7.)  Attempts/Successes On My Part
8.)  Alternatives
9.)  To Do
10.)  Thanks
11.)  Contact Info
12.)  Personal Note
13.)  Version History
14.)  Copyright Information


1.)  Introduction

So, you've been bitten by the nostalgia bug or the retro bandwagon has run
over you at full speed.  You've got a NES in front of you, and shiny, yet
scuffed, copy of The Legend of Zelda in your hands.  You pop the cartridge
in, play for a few hours, save, and shut down.  After going about your 
business, you turn the NES back on, only to find 3 blank save spaces.  
Everything is gone.  EVERYTHING.

So, what do you do?  The last I'd heard, Nintendo no longer replaces 
batteries in NES cartridges.  And what if you're not a wiz with a soldering 
iron or have never touched one in your life?  No problem, you won't need
one.  The process that I'm about to lay out for you will require only a 
small amount of parts and time.

2.)  Disclaimer

The information that follows is based upon my own, personal experience.
I am in no way responsible for any damage to your cartridge, system,
property, person, or those around you.  You perform the following procedure
explained in this FAQ at your own risk.

At the time of this document's writing, I have used this procedure once.
The attempt was performed on a Legend of Zelda cartridge, which I have been
the original owner of since 1988.  The attempt was successful and this FAQ
is written from the knowledge which I have gained from it.

3.)  Tools and Material

3a.)  Tools

-Precision screwdrivers
-Side-cutters (Preferrably small, but sharp.)
-Crimper for small-gauge wire (Needlenose pliers can be used.  See 5.)
-Needlenose pliers

3b.)  Material

-Small-gauge wire, stranded, approximately 2' (You won't need it all.)
-Crimp-on female disconnects
-Electrical tape
-Battery holder for CR2032 battery (Preferably surface-mount.)
-CR2032 battery
-Game cartridge

4.)  Preparing the Patient

As with any electronics project, you'll want a clean, clutter-free
workspace.  As there are few tools and material involved, this shouldn't be
difficult.  However, for smaller parts, such as the cartridges screws, I'd
recommend using an old pill bottle cap for storage.  While sticking them in
one half of the empty cartridge case is fine, at some point, you will be
reassembling the game.

NatashaQuick of the GameFAQs Message Boards recommends using a small magnet
to hold loose screws during the process.  Thanks, Natasha!

(Author's paranoia at work:  Don't keep the magnet near the battery.  I'm 
not sure about lithium batteries, but magnets drain alkalines.
I'd also recommend not leaving the screws attached to the magnet for days
on end, as the screws will eventually become magnetized themselves.)

5.)  The Operation

5a.)  How it SHOULD be done.

Begin by removing the screws, setting them somewhere safe.  Open the case
and either set the whole thing aside, or use one half to keep your project
all in one spot.

Looking at the board with the contacts facing toward you, take note of
where the terminals contact both the battery and the board.  The contact
that is soldered to the top of the battery and the right side of the board
is the positive (+).  The contact on the bottom of the battery, soldered
closer to the center of the board, is the negative (-).  Make yourself a
note or a diagram.

With a flat screwdriver, gently pry the positive terminal up and away from
the battery.  Don't try to brute-force it off of the battery.  Though it
can probably be broken free, you won't be needing all of the terminal and
you don't want to damage the negative terminal.  Once you've got enough
room, snip the terminal at or below the bend with the side-cutters, leaving
yourself at least  1/4".  Repeat the process with the negative terminal.

Now, you'll need to prepare your wire and disconnects.  I would recommend
a length of about 6" per wire, though you could probably get by with less.
Strip the ends about 1/4"-3/8".  Slide the disconnect over the wire, until
the exposed wire starts to come up through.  Using your crimpers, squeeze
the plastic end of the disconnect until you're sure that the wire will no
longer be able to come loose.  Once you've gotten two on each wire, you're
almost done.

Slide one end of each wire onto the battery terminals.  Though they may
fit perfectly snug, they may still need a bit of tightening.  If you
couldn't find the most narrow disconnects available, they may require A LOT
of tightening.  This is not a major issue, and one that's easily remedied
with a set of needlenose pliers.  While attached to the terminal, grab the
metal end of the disconnect widthwise and gently squeeze it tight.  There's
no need to go ultra-tight.  Just make sure that it fits snug enough that 
something as simple as a fall will not jar it loose from the terminal.

For the battery holder, perform everything the same as above.  The battery
holder I used was a surface-mount piece, which provided the terminals with
which I could connect the disconnects to with no problem.  If you didn't
get the narrowest disconnects, it could lead to later problems with closing
the game's case.  Without modification and bending, the larger disconnects
sit at a more extreme angle.  The smaller disconnects make the job as a
whole much easier.

Before trying to close the case, you'll need to do two things:  wrap the
disconnects with tape and fold the terminals down.  Again, this is easy,
but don't be brutish.  The reason for the wrapping is just to prevent any
shorting that could occur due.  In my case, it was probably more necessary.
After you've covered the exposed metal of the disconnects, fold the
negative terminal down, angling it a bit to the left or right of it's
original position.  Doing so will allow for more room for the positive
to do fit.  Repeat with the positive, angling in the direction opposite of
the negative.

From here, all you need to do is put in your battery and close up the case.
Once your battery is in, fit the cartridge into it's usual spot.  As far as
the battery holder, you can either tape it to the inside of the case, above
the board, or let it sit free.  I would recommend taping it.  Close your
case and you're ready to breathe new life into your once-dead game.

5b.)  How I did it.

A hasty hand and an anxious mind wreak havok and leave you without pictures
of the battle.  So now I'm kicking myself for not being able to put a photo
essay/tutorial up.  That's okay, I'm sure I'll be doing this again in the
near future.

Okay, I have everything prepped.  For my wire, I used a Cat 6 patch cable.
Unbeknownst to me, it was made using solid wire, rather than stranded.
This is no big deal, as long as you're careful, but it can be a pain.
Solid wire will break after much fewer bends and is stiffer than stranded.
Also, it was a 24-gauge wire, which is a few gauges smaller than the
disconnects allow for.  This is no problem.  It just requires a little
more care.  When it came time to crimp on the disconnects, I simply made
sure that I stripped around 3/4" off the end of the wire, and folded it over
on itself.

Another issue I had was that I had lost track of my crimper.  Not to be
put off, I used needlenose pliers.  They worked fine, but again, it took
more time and effort.  The result was that the plastic sleeve over the
crimp end came loose.  So, I just let it slide off of the wire, crimped
the metal (which was more like getting it's seam to seperate, and rolling
it over itself), and it was on.  This lead to a problem, though, with the
second crimp on each wire.  While I was able to remove one sleeve before
putting it on the wire, I usually ended up twisting the terminal end off
completely or bending it into a mess.  Trial and error.  So, I crimped it
on and cut the sleeve from around the wire, careful not to cut the wire
itself.  Needless to say, before I try this particular replacement again, 
I'm going to make sure I have all of my tools handy.

Having lost the sleeves from the disconnects, covering the disconnects
became all the more important.  I didn't know what I'd done with all of
my electrical tape, but I did have self-fusing silicone splicing tape.
Granted, it won't leave a mess like electrical tape, but it costs about
10x more ($0.65 as opposed to $6.50 or higher).  So, unless you plan on
removing the tape repeatedly, stick with electrical tape.

I'm also not completely happy with my choice of battery holder.  It fit,
but just barely.  I'm sure I could have done more to make it fit better,
but we'll just have to see.

6.)  IT'S ALIVE!

Now, you've got your battery installed, your case closed, and you're ready
to play.  Pop that sucker into your NES and power up.  Things should be
perfectly fine, assuming you've kept your positives and negatives straight
and made sure that there were no possibilities of shorting out in the cart.

If you want peace of mind, you might want to take a deep breath, fire up
the game, play long enough to save, shut it down, pull the cart, and let
it sit for a while.  Personally, I'm a patient person and had plenty to
keep me busy, so I didn't get to make sure it held the save for a full two

So, now that you know all is well, pat yourself on the back and go play!

7.)  Attempts/Successes On My Part

Attempt #1:  The Legend of Zelda
Status:  Success
-24 AWG solid-conductor wire (taken from Cat 6 networking patch cable)
-3M self-fusing silicone splicing tape (part # unknown at this time)
-Crimp-on female disconnects (part # unknown at this time)
-CR2032 battery holder
Manufacturer:  Keystone;  Part #:  1061
Purchased from:  Allied Electonics (alliedelec.com);  Stock #:  839-1061
Price:  $1.27 ea

Personal Critique:

Functionally, everything is fine.  I set out to see if I could perform
a solderless battery replacement without modifying the game's case, using 
what was available to me.  To that end, I succeeded.

I had really planned on taking photos and making an easy-to-follow visual
tutorial, but got in too big of a hurry.  My haste also made the job turn
out perhaps not as clean as I would have preferred.  Really, though, with
what I had on hand, I can't say that it would have looked much better.

In the end, the cartridge retains saves and doesn't have a battery pack
hanging off of it's back, so I'm happy.

Future attempts will be better planned and result in cleaner work, but the
overall procedure will remain the same.  That is, until I've gotten my
soldering skills back up to snuff.

8.)  Alternatives

-Female Disconnects

In lieu of the disconnects, you could simply try punching holes through the
existing battery terminals, leaving you with holes on both the board and
the battery holder that you could run your wire through, twisting and taping
it in place.  However, I really would not recommend trying.  Punching the
holes could prove not only awkward, but could potentially destroy the game
you're trying to resurrect, or worse, you could end up with a nice sharp
object through your hand.

Unless you're going to move up to soldering, I'd advise you to stick with
the disconnects.


As long as you've got something preventing your terminals/leads from hitting
making contact with those of other components, you're safe.  There are
female disconnects that are fully insulated, from the crimp end, all the way
to the connection end.  While these would be great for the board side of
your wire, the plastic is rather thick and is molded so that it's not very
close to the connection end, making it difficult to attach to the battery
holder's terminals.  The fully insulated disconnects could also prevent the
battery holder from fitting in the cartridge.  As you'll be positioning
the battery holder away from anything conductive, you shouldn't need to
insulate the battery end of the wires.


I've recommended the use of stranded wire.  You can find a small-gauge
hook-up wire at Radio Shack for relatively little cash.  I wouldn't use
anything heavier than 18 gauge, and even that may be a bit much.  I'm no
electronics expert, so I'm not sure if there would be any extra added
resistance for using a thicker wire than I used.

Whereas solid wire is a single piece of copper, stranded wire consists
of multiple strands of wire up to a particular gauge.  Solid wire will be
used in instances where movement is not a factor.  Stranded wire is used
in items such as power cords, extension cables, and networking patch cords.
Stranded wire withstands more bending and is much less rigid than solid

I only recommend stranded because it can save you some possible headaches.

-Battery Holder

There are always alternatives.  Taping the wires directly to the battery
is fine and would provide for much less of a space concern.  Simply
stripping the ends about half an inch, touching them to the appropriate
side, and wrapping the whole battery a few times with electrical tape
would work fine.  Of course, you may need to clean the wires when it's
time to change the batteries out, but that's a concern that would only
come up every few years.

(While anyone who's had some experience goofing off with batteries, wire,
and motors or lights could have come up with the above solution, the use
of tape to connect the battery was previously covered in a FAQ by
Kirby Freak101.  Kirby Freak101's SNES Battery Replacement FAQ is located 
in the SNES Hardware FAQ section at www.gamefaqs.com.)

My own choice of battery holder was out of asthetics and what was out there.
Having done some extra research, I've found another battery holder which
would most likely hold the battery in place just as well, not to mention
costing $1 less and taking up less space in the cartridge.  In fact, the
placement of the surface-mount soldering lugs on them would allow for the
disconnects to seat flat, rather than at the angle that they did on the
model that I used.

So, for later attempts or where space is a concern, I'm going to try this:

Manufacturer:  Keystone;  Manufacturer's Part #:  3002
Purchased from:  Allied Electonics (alliedelec.com);  Stock #:  839-0385
Price:  $0.25 ea

9.)  To Do

-Gather remaining part #s.
-Buy a few more games that use battery-backed saves and repeat the process.
-Create ASCII diagrams of parts and as visual representation of the process.
-Expand into the use of AAA batteries, soldering, and case modifications.

10.)  Thanks

-All of those who aren't afraid to modify, repair, or otherwise Frankenstein
their gaming equipment for the sake of fun and enjoyment.

-www.gamefaqs.com:  There's a lot of knowledge to be had.

-www.byoac.com:  Even if you don't want to build an arcade cabinet or
gaming control panel, there's plenty to learn that can be applied elsewhere.
The community that surrounds this site is unparalleled in cooperation,
assitance, and kindness.

-The H2SB:  For constantly reminding me how old I am and being a great
bunch of misfits.

-NatashaQuick:  With your informative and helpful posts, you've quickly 
become one of my favorite cohabitants on the GameFAQs boards.  

11.)  Contact Info

In regards to this FAQ or any other FAQs I may write in the future, I can
be reached at the following e-mail address, with the proper items replaced
and spaces removed:

dbfaqs at gmail dot com

In order to keep things easy for me, please include this as your subject:

Solderless Battery Replacement FAQ

Do not use subjects such as "OMG, puhleeze hep meeee!!!", as these will
most likely be deleted.  Demands or general rudeness and/or impatience will
also result in deletion and no reply from me.

I have done my best to make sure that the information provided has resulted
from my own work.  The procedure which I devised and implimented was my own
and was not taken from anyone elses work or suggestion.  One recommended
alternative resembled that of a previously posted work, therefore credit
was given to the author of said work.  If any other item such as this
remains uncredited, please feel free to contact me.

Feedback, questions, and constructive critisism are always welcome.  If you
have anything to add, don't hesitate to share.  However, if it's an
entirely different process, rather than just a helpful tip, I suggest that
you write a FAQ yourself and get the full credit that you deserve.  

12.)  Personal Note

This is my first FAQ and I think I did okay.  Could I have streamlined it a
bit?  Probably.  Personally, I like to provide as much info as I can in
a manner that is comfortable and almost conversational.  I've read some
FAQs and tutorials that get so focused on trying to sound professional
that they actually end up leaving out some details.  You'd expect a
beginner who is following the directions to miss a step, but not the
author.  When you have to print 3 different FAQs to accomplish one task,
nobody wins.  

I want this FAQ to be easy to read and understand, and above all, I want 
it to be helpful.  A little electronics knowledge can go a long way,
but not everyone has that.  If I've helped anyone who has only a
handful of tools and no soldering iron skills, then it's worth it.

13.)  Version History

V. 1

-Began February 6, 2006.
-Created contact e-mail address specifically for FAQs and contribution
questions and issues.
-Flow, layout, and 75% of content completed February 6, 2006.
-Content completed February 7, 2006.
-Submitted February 7, 2006.

V. 1.1

-Began update (after putting it off for months) on June 15, 2006.
-Updated Section 4. Preparing the Patient with a tip from NatashaQuick
of the GameFAQs Message Boards.
-Updated Section 9. To Do.
-Updated Section 10. Thanks, adding NatashaQuick.
-Updated Section 11. Contact Info.  No update to pertinent info, just
more jabbering on my part.
-Updated Section 13. Copyright Information, adding neoseeker.com to
the list of sites with permission to host this FAQ.  This FAQ should
be available on that site shortly.  Useage info was also tweaked to
sound less awkward.
-Changed Section 12 to Section 13, Section 13 to Section 14, created
a new Section 12 "Personal Note", altered Table of Contents to reflect
all changes.

14.)  Copyright Information

This FAQ is Copyright (C) 2006 DarkBubble.

Permission to host this FAQ is granted to the following site(s):



This guide is for personal use only and may not be republished
elsewhere in any form without expressed permission of the author.