Replacement Rechargeable Batteries Needed 3.7V 220mAh

I am need of about 300 replacement batteries. I don’t know if I have to get the exact battery that was originally used or if something similar would work? I would want the batteries to be the same or better, and of course most importantly be compatible with the device. These are for Innotek Electronic Dog Fence Receivers models IUC-5225 and IUC-4225. Below is the info from the original battery. Thank you for your time.

3.7V 220mAh Li-polymer Battery H622025

  1. certification:UL,CE,RoHS,SGS,ISO9001,ISO14001
  2. dimension: 6.2mm20mm25mm
  3. voltage: 220mAh
  4. OEM welcome

Specifications:
Typical capacity: 220mAh
Nominal voltage: 3.7V
End voltage: 2.75V
Charging current (Std.): 0.2CA (=44mA)
Charging current (maximum): 1.0CA (=220mA)
Charging voltage: 4.20 ± 0.025V
Charging time (Std.): 6 to 7.0 hours
Charging time (maximum): 2 to 3.0 hours
Continuous discharging current (maximum): 220mAh
Discharging current (maximum.): 440mAh

Hm. I’m not seeing any obvious termination on this part, save for those two small prongs towards the top. Does this look like a custom battery pack to you, by chance? Something made specifically for these dog fence devices? Or is there a standard battery cell or two inside a housing I’m not seeing from the provided image?

Hey Matt,
Thanks so much for your reply. I’ve uploaded some pics. You can see the two small terminals. The photo of just the battery has only one probe because the other broke off, but you can see what it looks like. Ya, the ones I usually see have those black and red wires coming from them. I don’t know if this is how they come before those wires are attached?
That’s kinda where I’m stuck… knowing what specs need the batteries have to be to make sure they are compatible, and finding batteries that have those terminals instead of the wires (or finding a work around for that).

1832-1032-ND is the closest I found, may be too big however or not work with original charger, please verify before ordering.

Most of the battery packs of this type I’m seeing, Options here, are wired and connectored. I’m not quite seeing how this one terminates, save that it looks like it might be pin directly to board? Sorry, the pictures are playing tricks on my eyes right now. if it is direct pin-to-board, I’d probably be seeing about contacting the manufacturer of your dog fence devices to see what they can tell you about these parts, as it looks like this battery pack has some built-in circuitry between the battery cell and the PCB that one of our packs might not be able to replace.

As far as the specs for the battery, How do you determine what will be a compatible replacement? Does it have to be 3.7? Could it be any mAh? So for example if the battery fit, could it be 3.7V and 600 mAh?

Voltage should be identical, yes. Plugging more or less than the voltage a system is expecting into its Vss slot could potentially damage or destroy your devices.

‘mAh’ is basically a measurement of battery life; in this case, higher mAh is pretty strictly better, all else being equal. A 600mAh battery would last almost three times longer between charges than a 220mAh battery, provided it physically fit and there were no other factors affecting its discharge rate.

Most of the other specifications for your battery that you’ve given are in the realm of secondary engineering concerns. It’d be nice if you could try to match or exceed the end voltage of 2.75V, in case that’s important for a monitoring circuit inside the receiver, but that’s not a concern I’ve encountered before now. Elsewise you’ll want to match or exceed continuous discharge current capacity to ensure the battery can power what it needs to, and trust that whoever designed the circuit ensures the battery doesn’t swamp anything.

Thanks for the info Matt, I really appreciate your time. I’ll probably give one of those batteries you recommended a shot and see if it will work, and at the very least I’ll be able to compare them side by side.