> For the complete documentation index, see [llms.txt](https://key4.hideez.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://key4.hideez.com/guide-for-hideez-key/service-operations/battery-maintenance.md).

# Battery maintenance

Hideez Key comes with a pre-installed battery.

{% hint style="success" %}
In case your Key does not switch on, please, check if you [removed the white plastic](/guide-for-hideez-key/quickstart-guide.md#step-0-remove-isolating-material-from-the-keys-housing) from the Key's housing.
{% endhint %}

### Hideez Key 4 Battery 

To recharge the battery you need to plug a Micro-USB connector to the corresponding port located on the side of the fob. Wait until the LED indicator becomes green. Hideez Key 4 will be ready for work.

The lifespan of a lithium-ion rechargeable battery like the **LIR2032 3.7 V** can be influenced by several factors. Here are some key considerations: charge and discharge cycles, temperature, charge Level, overcharging and over-discharging, and quality of the battery.

While many factors can influence lifespan, a typical lithium-ion battery might last for numerous years under normal usage conditions.

### Replace the battery 

If for some reason you need to replace the battery, please follow the next instructions. 

The case is made of two halves latched together. 

To replace the battery, open the case and lift the gap between the halves with a fingernail or a plastic card. Do not use metal objects. Remove the old battery by pushing it from the inside using a narrow plastic object. Install the new **LIR2032 3.7 V** battery on the narrow side (minus contact) of the board. Hideez Key will start to work.

{% hint style="info" %}
**Hideez Key** **4** has a battery **LIR2032 3.7 V (RECHARGEABLE)**

**We highly recommend using the Hideez Key with the corresponding type of battery.** 
{% endhint %}

Opening the case.

![](/files/TYhEWKOe0InlEo6UxlT6)

Changing the battery.

![](/files/OoBzyOL4UYuK6XtNmrXu)

{% hint style="info" %}
Notice: if you don’t want to change the battery by yourself, you can contact any electronic service center that replaces watch batteries. 
{% endhint %}

![](/files/1QBMorDIKyPi6PWLexeB)