DIY Invisible Fence Battery





Introduction: DIY Invisible Fence Battery

Invisible Fence pet containment systems require a new battery in the dog's collar every 3 months. Invisible Fence dealers sell battery packs for around $15. This expensive battery is a plastic case around a common CR1/3 lithium cell, readily available from any hardware or drugstore for less than $5.00. Here is how to "renew" your battery in about 1 minute!

Step 1: Prepare Tools and Supplies.

You will need:
- A 3V lithium cell known as CR1/3N or DL1/3N
- A spent Invisible Fence battery module
- A razor blade, a sharp knife or a very small shovel
- Optionally, something to grasp the battery with to avoid cutting off your fingers.

Step 2: Grasp the Battery

Hold the battery sideways and grasp firmly

Step 3: Pry Off the Cover

With a very sharp knife, separate the cover ring from the battery housing.

Step 4: Separate the Cover

Gently work around the battery housing until the cover falls off. Be careful with the metal contacts! Note the orientation of the cell - the new cell will go in just like this.

Step 5: Pull Out the Battery Assembly

Gently pull out the cell by the metal contacts.

Step 6: Separate the Battery

Remove the cell from the metal clip. Discard the cell in the most environmentally-friendly way available.

Step 7: Insert New Cell

Put the metal clip around the new cell. Make sure the positive side of the battery only (the metal can) is in contact with the metal clip. Gently insert into the plastic housing, aligning the metal clip with the grooves on the inside of the housing.

Step 8: Check Battery and Clip Positioning

Make sure the cell is all the way in and is oriented correctly.

Step 9: Replace Plastic Cover

It will snap into position between the 2 metal contacts.

You are done!



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82 Discussions

Are you sure that the plastic ring is not needed?


11 months ago

I've been doing this for years, so I'll add a few tips: don't use a vise grip, use a soft jawed clamp. You don't want to over stress the sides of the container. The rings can also be glued back on if you want, using solvent cement such as for plastic models. Use a TINY amount. Also, periodically rub some silicone grease on the O-ring seals. They will last longer.

To those who are replacing batteries in IF Power Caps.  Though you may think that your saving a few dollars each time you install Non IF products, you will void all your warrantees!  IF puts a lot of engineering and professional designs into their products and support.  So, you may pay a little more for a power cap that makes sure your collar is working properly.  You are also guaranteeing that in the future, when maybe your transmitter fails, or collar receiver stops working,(probably due to your installing inferior battery and damaging the case) you will be charged for a new collar or transmitter( $200-$1000), when it would have been installed again for no charge at all.  I am an IF dealer who prides on our service and warrantee work.  I have installed warrantee repair even for dealers who didn't go out to fix their sold systems.  So, with that said, you call for service and batteries, you don't have to leave the house.  We are out there within 24 hours to take care of your issues.  I kind of think that I would rather have the comfort of knowing someone else out there cares about my pet as much as I do and at our dealership, that is how we think.  NOTE: when I looked at this way of installing new batteries, I was quite interested in the thought process, but also realized that no matter how you take this apart, you are damaging the case and weakening it.  It would only be a matter of time before the receiver would fail due to water penetration or corrossion of the receiver.  Good luck and I will be here to take your call.

6 replies

Bull, plain and simple. I've been doing this for fifteen years. IF just wants to rip people off. I had to redo part of our installation because the installers didn't follow my instructions—they knew better, really. After our 3 year contract ran out, we got a lot of calls trying to frighten us into renewing. However, my research, which I wish I'd done before installation, showed me how much a ripoff IF is. You can find as good, if not better, electronic pet fences just by looking. With three years of old battery cases, If one shows strain I can replace it. Getting that supply of cases was the only good thing about our experience with IF.

Warranty? What a sham! IF warranty is garbage. My collar probe fell off in just over a year when the housing plastic broke. IF denied warranty. What exactly is covered? You will find nothing in writing. Complete scam.

Yo Kingring1 - You know that a "power cap" is simply a 3V Duracell DL 1/3N Photo Battery right? $4.19 anywhere in town. I used to work for IF and did this all the time in a jam. If you do it right, the collar will be fine. Beats the $25 IF is charging for the "power cap". Use the right battery peeps and you'll be fine. As far as this comment --------> "IF puts a lot of engineering and professional designs into their products and support"... If they really did, they would engineer the "power cap" so you could easily replace the battery with the DL 1/3N and not have to drop $100 a year in IF "power caps".

PS Be sure to lube the "O" ring with a little plumbers silicone lube to keep it from drying up and cracking. That's all..

I've been doing it for years, except I pay way less than $4.19 per battery. I'm getting a CR1/3N ten pack from a place in TX called "Best Byte Computers, Inc. for $15! They charged me $3 for shipping (USPS), so the grand total for 10 batteries was $18, about what IF charges for 1! I understand what the dealer is saying, although you aren't "damaging or weakening the case" if you have the slightest knowledge of how to use tools. In fact, I think the vice grips are way over-kill for this plastic casing. But back to the dealer, and this isn't his fault, but if IF didn't charge an arm and a leg for their "power caps," many people wouldn't be searching for alternatives. I'm in business as well, so I have absolutely no problem with someone making a profit, but this is absolutely ridiculous. They could charge $5 each for these things, and still make a nice profit. Sorry, but sometimes the company asks for it. If you don't agree with me, then please answer this: why do you think $17 per power cap is a fair price? I just checked the IF web-site, and the price for one "power cap" is $16.99. Yes, I realize you can get the price down towards $13 each if you sign up for some kind of plan, but it is clearly too much.

Right on jcperea69, the whole invisible fence thing is a crock. The above fix works like a charm. You're right about the "engineering and professional design". As a matter of fact if they were really interested in attending to the customer and his pet, they could design a collar that beeps when the battery is getting low and have the collar rechargeable like the Sport Dog trainer collars. Now there's a company who cares. IF just wants to bleed you forever. I highly recommend the above work-around.

Here's the issue with that. I just called the IF company and said I would need somebody to come look at why my fence of ONLY 6 MONTHS wasnt working. The woman who answered said "Well it will be $80 for us to come look" Seriously you want $80 to see why YOUR fence stopped working after only 6 months?? I dont think so. Then she tells me Well you can sign up for our battery delivery for $69 and and we can see if that fixes it, since I hadnt changed it yet. I was not told the battery needed to be changed every 3 mohts and am FURIOUS I am just now finding out I have to buy this expensive battery of 3 months. I felt like our rep was dishonest to not mention this fact. I will NOT recommend this fence to anybody I know. I will tell them to go to petsmart like my neighbors tried to get me to do. They got their fence for $300 and the batteries are super cheap! And they have had it for 5 years and NO problems!!

"Batteries + Bulbs" had this battery in stock for $4.19 each. It was not carried at our local Walmart, Walgreens, nor CVS.


IF appears to have made a design change to their power caps to foil this DIY approach. The plastic cover ring you used to have to pry off with the razor blade is now more integrated with the battery container portion of the cap. It no longer sort of snaps off so you can snap it back in. You have to bugger it to get it to come off. Not to worry, the ring is not necessary. I just sort of chipped the ring away and put in a new battery and put it back in the collar without the ring. There is a spring in the bottom of the cap that keeps pressure on the battery. Despite the design change, you still can change the battery.

1 reply

yep all you need to do is open up the hole that exposes the battery with a utility knife large enough to liberate the battery. out it comes. swap with new 4 dollar battery and woolah! saved 35 bucks!

Took me all of 4½ minutes and 4½ dollars to pull this off. I too was told there would be an $80 service call fee after my system failed after 4 months. Although awfully expensive for initial investment, I will say that the system has contained our very adventuresome beagle, Max.

I just wanted to say thanks to everyone for all the information below. I was not pleased with the cost of the IF instal, then the collars were outrageously priced. Mine came with a one year battery replacement. I've had it 6 months. Found my little dog in the field/forest area behind my house and realized battery dead. this was a Friday. By the time I called them it was mailed to me on Monday, hence 5 days without so far. and I was told they were supposed to last 3 months. This was 2 months. She said my dog tested it more (probably true). Anyway, rather than wait, per instructions below I found one at Radio Shack (don't go there.... too expensive $15). I will try Ace next time or use the 2 1.5v suggestion below. I did as instructed and it worked perfectly. When using the razor blade, the bottom broke off into 2 pieces. i just tossed tham. I am thinking of moving. Is there a better service to use next time..

Thank you for these instructions. I followed them and it's much easier than it looks (I thought it would be tough to remove the end piece but it really isn't even tightly attached) I resolved my immediate need for a working IF collar in about 25 minutes (5 minutes opening the battery housing + 20 minutes driving to and from hardware store) The battery cost exactly $5.06. I was a little afraid it wouldn't go back together correctly but their really isn't anything that can get messed comes apart easily and goes back together just as easily.
I'm actually kinda mad at IF now that I see what they've been charging me vs what it's costing them to produce....argghhhh! Thank's again for these directions. From here forward, I'm keeping my money in my own pocket.

Just to let you know that this procedure voids the warranty on your receiver. It is easily visible that the battery has been tempered with and if there is a problem with the receiver and needs to be replaced you will have to pay to have a new receiver. Why?? Because these batteries can leak inside the receiver causing corrision or the battery may come apart and get stuck in the battery chambers.

2 replies

I've been doing it for years, and never once has a battery leaked. In fact, I live on a lake, and my dogs go in the water everyday during the warm months. Besides, who would go in for a warranty claim with a "power cap" that appears to have been tampered with? Just put in one of the rip-off batteries before going in...

Look up the "Magnusson-Moss Warranty Act" before spouting more barrotry.

I just found that (not Best Buy - Best Byte Computers)has these online for $2.55. If you order 12 they go down to $2.35. The shipping was USPS for $3.00.

I have three dogs, so I got twelve. That should last me a year!