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Home › Batteries › KECR2040
Coin battery

KECR2040 is the same as CR2040

1What it is2Safety3Other names4Facts5Buy it
  1. 1

    What it is

    CR2040+ 3V

    KECR2040 is just another name for CR2040. Same battery, different label, so you can buy either one.

    Search Amazon for KECR2040As an Amazon Associate, KnowYourBatteries.com earns from qualifying purchases.

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  2. 2

    Safety first

    Keep away from children and pets

    A swallowed coin or button battery can cause serious burns inside the body within 2 hours. If you think one was swallowed, get emergency help right away.

    Swallowed one? What to do now →
  3. 3

    Names you might see in the store

    All of these are the same battery. Any of them will work.

    CR2040DL2040ECR2040KL2040L2040L24
  4. 4

    Quick facts

    Size
    About the size of a nickel
    Thickness
    As thick as 5 credit cards stacked
    Power
    3 volts
    Keeps in a drawer for
    About 10 years
    Rechargeable?
    No, use once
    Found in things like
    AltimetersFlow metersOrganizer memory backup
  5. 5

    Where to buy it

    As an Amazon Associate, KnowYourBatteries.com earns from qualifying purchases.

    Amazon searchEnergizer listings, any pack sizeSearch Amazon for Energizer ECR2040
    See results on Amazon →
    Amazon searchMulti-packs from any brandSearch Amazon for KECR2040 (CR2040) multi-packs
    See results on Amazon →
    Amazon searchDuracell DL2040 listings, the same batterySearch Amazon for Duracell DL2040
    See results on Amazon →

    Buttons open amazon.com 🇺🇸, picked from your country.

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See it at real size

CR2040 next to a US quarter and an AA battery. “Real size” matches your hand once your screen is set up in Measure it.

CR2040Thickness 4.0US quarterAA

What do the letters mean?

Battery names are a code. Here’s how to read KECR2040:

KECREnergizer lithium coin
2040Same geometry as CR2040: 20.0 × 4.0 mm

The same battery from each brand

BrandTheir name for it
Official nameCR2040
EnergizerECR2040
DuracellDL2040
RayovacKECR2040

Exact measurements

Width
20.0 mm (0.787 in)
Thickness
4.0 mm
Voltage
3.0V (empty at 2.0V)
Energy stored
280 mAh
Weight
—
Made with
Lithium manganese dioxide
Works between
-30 … 60 °C
Official code
CR2040

Questions people ask

Is KECR2040 the same as CR2040?

Yes. They’re the same battery with different names. You might also see CR2040, DL2040, ECR2040, KL2040.

How long will a spare keep in a drawer?

About 10 years if it stays cool and dry.

Can I recharge it?

No. Never try to recharge it.

Which way up does it go?

Usually with the side marked “+” facing you or facing up. Look at how the old one sits before you take it out.

CR2040+ 3V
CR2040Coin battery
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1What it is2Safety3Other names4Facts5Buy it