DIY Philips Razor Battery Upgrade with 14500 Lithium

If you're interested in upgrading the battery of your electric razor, you might want to take a look at this article.

Philips electric razors typically require two AA batteries. If you're not planning to buy AA batteries, you can use 14500 lithium batteries instead. The image below shows the voltage after connecting a diode in series.

When powering on, the diode has a voltage drop of 0.85V.

While in use, the battery voltage is 3.4V, and even when it's fully charged, it will be around 3.35V after subtracting the 0.85V drop from the 4.2V charging voltage.

The battery voltage when not under load is also important to consider.

You'll need to connect a diode in series to make this work.

This way, you won't have to constantly stock up on AA batteries.

The end.