DIY Upgrade for SOLOVE F5 Fan Battery and Charging

If you're interested in modifying the battery and charging system of your fan, take a look at this article.

The SOLOVE F5 charging fan originally comes with a 4000mAh battery, but it's simply not enough to run the fan all night long. Additionally, the charging is slow, and charging while using the fan doesn't work well. If your fan is experiencing similar issues, let's go through the modification process together.

When you open up the fan, you'll find the following structure:

The original charging system uses a TP4056 module, which can only charge at a maximum of 1A. This makes charging while using the fan impractical. To solve this, you can use two additional TP4056 charging boards to increase the current. The default current is 1A, but if you find that it generates too much heat, you can add two 1k resistors from the charging board (which limit current for the LED) in parallel and then in series with the default 1.2k resistor. This brings the total resistance to about 1.7k, resulting in a current of roughly 0.7A per board. With two boards in parallel, the current reaches 1.4A, plus the original 1A, giving a total of 2.4A. This current can be handled by most charging heads without overloading the charger. Another advantage is that it helps control the heat.

The two boards are stacked as shown in the image below.

For the battery, you need a high-capacity one. The original two-cell battery position has been expanded to three cells. You can choose Panasonic 3200mAh batteries, which will give you a total capacity of 9600mAh when connected in parallel. This is enough to power the fan throughout the entire night.

Since the battery has a higher capacity, it won't reach the maximum current during use.

Once the battery is depleted, recharging at 2.4A completes the process.

Done!