Broken CMOS Battery Holder ML1220

I accidentally broke the CMOS Battery Holder.

Here's with the battery:



Here's with the broken + (positive) contact side:



Here's with the + (positive) contact side removed to reveal a black pad(?) underneath. Is it a contact pad? There's no glob of solder holding it down, like on the - (negative) side. (See first picture with battery to see the - side solder.) I'm just wondering how the contact is made.



I found the exact replacement here:

https://www.digikey.com/en/products/detail/keystone-electronics/1072/9921820

and schematics here:

http://www.keystoneelectronics.net/ENG._DEPT/WEB_ORACLE/PDF/PDF CAT NO DRAWINGS/1000-1999/1072.PDF

I can't tell from the schematics how the battery holder is attached to the motherboard. Is it two solder joints? One on each side of the battery holder? Do I just put a dab of solder underneath the + side?

Anyone familiar with this type of battery holder?

Motherboard is an Acer Aspire 1410 (1810T) netbook.

 

Hello,

It seems like a part of the PCB track is brocken too.
If i was you i'll replace it with a vertical CR2032 holder and solder 2 wires (one for the + and one for the -)
Have a look at this with this kind of holder you just have to cut the white connector, and solder + and - and use some electronic tape to cover the visible part of the CR2032.
With this is place, you'll just have to remove the tape from CR2032, change it and take back the tape.

If you're not familiar with soldering, you may ask an electronic part repair, it doesn't seems to be very hard. I think it's way easier to solder 2 wires than the same holder that was on the board. Plus as i said PCB track seems brocken.

 

Thanks for the response!

The original battery is an ML1220 Rechargeable, so to introduce a CR2032, I would need to add a diode to prevent the recharging. Since this is inside a small netbook and the motherboard is multilayered, I don't think I can easily do that. However, if I can find a similar holder for the ML1220, that might do it.

The first question is whether the black pad underneath the + side is the conductive contact point and I need to expose the metal underneath? I'd rather not scrape something off that should be there. The - side has some solder to hold it down, but the + side didn't appear to have any and the bottom of the broken part just has a square metal pad.

Currently, the black pad doesn't appear to be conductive at all.

Black pad in question:



Bottom of broken + side. It's just a square metal pad that is conductive: (Was it just held in place with some kind of conductive glue, whereas the - side uses solder?)

 

Here are the two sides of the replacement part:

The + (positive) side doesn't have much clearance for soldering down a bead of solder. Maybe put some solder on the contact pad and heat up from above to make the connection?



The - (negative) side has plenty of space for solder:

 

Hello,

CR2032 and ML1220 have same voltage, ML1220 is rechargeable you're right and ML1220 is indeed smaller.
Seeing your last photo of post #3, you can see the copper from the track still soldered to the part of the holder. That's why you see the black/metal plate you circled in red with an arrow. What remain of the track is on the right of your red rectangle.
There are soldered ML1220 with wires already protected with protective tape like this and it'll be a lot easier to solder.
If you're not sure on what to do or not familiar with soldering, you may ask an eletronic part repair. It seems to be more difficult since one of the track is brocken.

 

The design of that socket looks inherently weak and subject to the breakage you experienced. Rather than trying to replace the socket, perhaps the easiest way to fix it might be to solder the female side of one of these pigtails to the motherboard:
https://www.ebay.com/itm/10-PCS-Micro-JST-PH-1-25-2-PIN-MALE-FEMALE-PLUG-CONNECTOR-WITH-WIRE-CABLE-M578/233719768767?ssPageName=STRK:MEBIDX:IT&_trksid=p2057872.m2749.l2649
...and use this type of CMOS battery:
https://www.ebay.com/itm/Yellow-Res...906053?hash=item3d524ee085:g:gX0AAOSwM3hfg9fU

 

Hey @Mr. Fox Thank for confirming my idea is good.
So @nrvinh your best bet is to find an ML1220 like me and @Mr. Fox said and solder it.
Do not try to remove what remain of the - part without a soldering iron and for the + you must remove it to have a better access to the - track.
I recommand you a very thin 10-15w soldering iron and a multimeter to check cuitinuity of your soldering. Also you must be very carefull with nearby component.

EDIT : Or you can try to break the big black round part and keep what remain of the + side, and use what did contact to the ML1220 as a soldering plt for the + wire of your new ML1220 part.
Hope you'll understand, it's hard to explain in english.

 

@Shin Falcon I think you're right about the trace being broken and the contact pad being ripped off the motherboard by the broken half of the battery holder. I took some more pictures... Thanks again for the observation and advice!

@Mr. Fox Thanks for the advice and link to the pigtails. I hope I can find an ML1220 Rechangeable that has the connector, to make for easy future replacement.

The black pad should probably stay to prevent electrical contact with what's below it. It seems there's only a sliver of the trace from the motherboard going to the missing contact pad that used to be over the black pad. I was able to test electrical continuity between the left and right side of the sliver. I guess I'll need to scrape off some of the green motherboard coating on the sliver to provide more surface area to solder to:



Here's the ragged edge of the square pad:



The battery side of the broken part, showing some solder:



A little lower angle:



Opposite side of battery of battery holder. The original contact pad is super thin!

 

Well, here's my attempt at the repair... first, the easy part, prepping the battery...



Positive and negative contacts taped down with foil tape, which contours very well around the wires. The adhesive prevents the charge from passing through, so although metal...



Wrapped with non-conductive electrical tape...



Shrink wrapped to make sure it stays together...

 

Now the motherboard... which I can't be sure worked...

The battery holder removed... missing positive pad on left, negative pad on right with some residual solder...



Some of the coating scrapped away to expose the trace to the missing positive pad. Negative pad cleaned of solder with desolder braided wick...



Battery connector soldered...



Since there wasn't much metal to solder to and the solder joint is weak, I decided to reinforce with non-conductive electrical tape to hold it in place...



Wider view with battery connected...

 

After reassembling...

Since my netbook doesn't have a 3M module, the space is empty, so I routed the battery connector into the pocket, to make RTC/CMOS battery replacement easier in the future.

The netbook still doesn't POST though! It's pretty much in the state as before, powers on with blue status light and power button LED blue, fan starts up, but no hard drive activity or LCD display.

So, either the positive wire didn't make electrical contact, the problem lies elsewhere, or the replacement battery is a problem, as it came as 2.79 V, not 3+ V. Could the battery be a problem? The seller assures me that anything above 2.7 V is fine. (The old battery is 2.9 V.)

Also, is there any way for me to check the connector to the motherboard?

 

The system should function normally with no CMOS battery at all. The CMOS battery is there to save BIOS settings when power is removed from the motherboard. When you say "in the same state as before" do you mean before you broke the original CMOS battery holder? Were you trying to remove the CMOS battery for replacement of the battery or to reset the BIOS to defaults?

I doubt the problem with the system not booting correctly is related to this. I would suspect some other problem.

 

Yes, before I broke the battery holder, trying to replace just the battery. When I lifted the battery, the battery holder lifted with it. The positive contact pad was ripped off the motherboard. The reason I tried to replace the battery was because it's 11 years old and I was told that sometimes computers don't POST if the battery is bad.

Boot goes like this:

1. Press power button and button lights up blue.
2. Blue status light at front of netbook is blue. It's the LED with the light bulb icon.
3. Blue lock light flashes on for an instant. It's the LED with the lock icon.
4. Fan spins up.
5. Netbook immediately powers off. Sometimes, it doesn't power off and pressing the power button for any length of time does nothing; the battery needs to be removed.

I haven't tried removing the RAM, to see if it'll POST without it.
I haven't tried removing the hard drive, to see if it'll POST without it.

The main problem right now is trying to figure out a debug procedure to diagnose the problem.

 

It is hard to know what the problem is based on the information regarding the symptoms, but I think it is pretty safe to conclude the issue is not being caused by the CMOS battery. If the computer is 11 years old it could be many things.

I have never seen a system that would POST with no RAM installed. If this just started out of the blue with no previous issues noted the first thing(s) I would suspect is a mechanical hard drive failure, GPU (if it has one), or a failed motherboard component. It could be a failed memory module, although less likely than the other possibilities mentioned. If you suspect the memory, test one module at a time in each slot. It would be extremely likely that both modules would fail. I would start with the hard drive removal.

 

The problem started out of the blue. The only "issue" prior was getting a warning from the OS that the battery had only 45% capacity left. When the problem appeared, I thought it might be the battery, but tested with wall power only and the netbook exhibited the same problem. I decided to buy a new battery anyway, just in case. The new battery didn't solve the problem. That's when I started looking into other issues...

This led me to here and the discussion over RTC/CMOS battery. I saw some other posts with laptops/desktops having issues POSTing without a good CMOS battery; that led me to buy a new CMOS battery and accidentally breaking the battery holder...

GPU is integrated graphics.

I tried removing the RAM and same result. There's only one module, so unless I buy another one, I have no way of testing.

I tried removing the hard drive and same result.

The thing that's bugging me is that the new CMOS battery is 2.79 V. The old one is 2.9 V. It should be 3 V or more, from what I've read.

 

I use laptops with no CMOS battery all of the time to facilitate the quick and easy clearing of NVRAM by simply disconnecting the AC adapter. The only issue people should/would have is a lag in booting while the BIOS re-establishes bootable settings, trains the memory, etc. So, the minor variation in voltage isn't going to keep your system from booting. It is unlikely that the RAM is bad and if removing the HDD did not correct the problem, it is more likely than not the motherboard has failed.

 

I confirm what mr Fox said, the CMOS battery is here only to keep your CMOS setting. You can boot normally without it and the only real problem is losing your date and time setting.
Try with just one stick of RAM and let it run for 1-2 minutes. If nothing appear, try an other stick. If it's still not booting, motherboard has failed.

 

This is an old thread that I read about CMOS battery issues:

https://steamcommunity.com/discussions/forum/11/618460171318429760/?ctp=2

I'll see if the battery seller can send me another battery with the voltage tested beforehand to be 3 V or better. The thread indicated that lithium batteries will maintain 3 V or better, then drop rapidly when it nears the end of its life. Any experience with CMOS batteries nearing the end of their life?

I'll see if I can find a cheap old Acer Aspire 1410 for parts...

 

I only have one memory module, so unless I buy another one, I can't test. I'm not sure how much further down the rabbit hole I should go, especially if it's a motherboard fault.

 

As i said, dead battery mean losing date and time setting. Never had a failed system due to missing CMOS battery since 1998.
You may have said us your laptop is not booting, our answer will be that your holder and CMOS battery is not the problem.

EDIT : searching for spare parts can be nice if you have the money. If your laptop is very old, parts can be hard to findand/or expensive.

 

I may just have to put this netbook on the back burner until I find another one that's parts only and hope the motherboard is good...

 

Just get a cheap DDR SO-DIMM (even 1GB stick will serve the purpose) on eBay for testing. It is possible, but not likely, that the RAM is bad. If you have two RAM slots, find one that matches your existing module, and then you can run in dual channel if you end up fixing the laptop.

 

You can find on Ebay some working Acer 1410 at 65€, found one this morning from Germany with 1Gb + Celeron 743. This is clearly an old and not powerfull laptop, not sure why you want to repair this one but i recommand you to search on ebay.

 

Well, if the problem was just the battery, then it's worth the effort, but it's looking more problematic, so it's perhaps not worth continuing... hard to say...

 

I bought another Acer 1410 with the same specs, minus HD and charger for $40 + $10 shipping from eBay. I swapped over the motherboard and now everything is good. I have spare parts for everything now, minus a second working motherboard.

 

Check the old motherboard with a new CMOS battery. Some poorly designed netbooks play dead without charged CMOS battery; stumbled upon this repairing one ASUS abomination.

 

Thanks for the response. If you look from the the beginning of the thread, I've already gone down the CMOS battery route. It was the third thing I tried.

- pressing the power button for a long period of time
- replaced the main battery
- replaced the CMOS battery
- tried a new memory module
- redid the thermal paste for the heat sink
- replaced the motherboard

 

@nrvinh you mentioned the replacement battery was 2.7V. I am suggesting trying a fully charged battery.

 

Ah. The complication right now is that I can't test to make sure my battery holder workaround is actually working properly. The pad was lifted and I think I found the contact trace on the motherboard, but can't be 100% sure.

I suppose I could try the 2.7V battery in the working netbook and see if a battery makes a difference, whether the netbook will POST or not.