The CR 2025

[lightseeker2009]

Can I please get some information about these batteries.
What voltage is acceptable when it is new?
At what voltage should you replace them? I supose it depends on their usage?
Lets say it is for a car remote key. Should they still work in car keys if giving a voltage reading of 2.8V?

 

[TinderBox (UK)]

I just bought 10 Maxell ones from ebay with 2018 expire date for £1 delivered , I tested four of them with my dmm and most were around 3.3volts i was expecting at least 3.5volts i have been using these my 3d glasses for my TV, I also bought some rechargeable Lin-ion 4.2v 2025 with a charger from ebay they are only 20mah capacity compared to lithium 165mah.

Also 2025 are supposed to be good down too 2.00volts, but it depends on the voltage-cutoff of the device, next time you get a low battery measure the voltage and then you will know.

John.

 

[lightseeker2009]

Oh no. So if my remote is not working, while the battery is at 2.8V, then it is not the battery's fault.
I so hoped that the answer could have been your battery is flat.
Thank you Tinderbox

 

[TinderBox (UK)]

I am not sure how much dead cat bounce the voltage of lithium have, meaning does the voltage level will recover/increase when it is not in circuit, it`s best to measure the in device voltage really.

Or you can buy a battery tester i have a digital one i got for £40 and it tests the battery under simulated load conditions so you get a more accurate idea of how much power is left in your battery`s

John.

 

[tobrien]

i believe i've had issues with coin cells when they got around 3.0v and below. besides, 2.8 volts is about dead for a CR123 anyways

 

[mcnair55]

I have a traffic light battery tester for coin cells,red is dead,amber still ok and green is good,had it years from Tandy UK (Radio Shack) and is accurate i have found.

 

[Lithium466]

My car key has 2 CR2025 cells, it was not working properly anymore with ~3,02V cells (I think this is the resting voltage). New Panasonic cells I put were around 3,25V.
I'd say 2,8V rested is pretty much dead.

 

[mcnair55]

My car key has 2 CR2025 cells, it was not working properly anymore with ~3,02V cells (I think this is the resting voltage). New Panasonic cells I put were around 3,25V.
I'd say 2,8V rested is pretty much dead.

Many garages have a little gadget that tests your key fob is working correctly with regards to sending and battery condition and usually is done when your car requires a service.

 

[Poppy]

My car key has 2 CR2025 cells, it was not working properly anymore with ~3,02V cells (I think this is the resting voltage). New Panasonic cells I put were around 3,25V.
I'd say 2,8V rested is pretty much dead.

I'd agree with this statement.
I just bought a card of 4 or 5 2032 coin batteries 3.0v. I pulled one out and it measured 3.5 volts.

 

[Lithium466]

Voltage sag of these batteries seem quite important compared to say CR123a.

 

[lightseeker2009]

My car key has 2 CR2025 cells, it was not working properly anymore with ~3,02V cells (I think this is the resting voltage). New Panasonic cells I put were around 3,25V.
I'd say 2,8V rested is pretty much dead.

You are 100% right. I put in two new batteries and everything is just fine.
I still can't believe just 0.6V (two batteries) can make such a big difference.
My advice: When your car's remote does not work, don't take it to the manufacturer. Just replace the batteries first:thumbsup:

 

[ShineOnYouCrazyDiamond]

Reading the open circuit voltage of a lithium cell is worthless. They don't change voltage much over their lifespan. You really need a battery tester that will check the battery under give circuit load to see if it has juice left in it. Only through a load will the voltage across the +/- terminals tell you the remaining capacity (button cell or CR123).

 

[archimedes]

The ZTS MBT-1 has a calibrated "load test" for the CR2025.

 

[ShineOnYouCrazyDiamond]

Thanks archimedes. I was going to mention the ZTS but was blanking on its name.

 

[archimedes]

Thanks archimedes. I was going to mention the ZTS but was blanking on its name.

Certainly ... I find it very useful to have the ZTS, in addition to a good multimeter.