# How to Make a DIY LiPo Charger: A Practical Guide with Examples

Have you ever found yourself in need of a reliable and safe way to charge a single LiPo cell for your electronic projects? If so, you're in the right place. In this post, we'll explore how to make a DIY LiPo charger using readily available components and practical examples.

### Understanding the Problem

As electronics enthusiasts, we often encounter the need to power our projects with rechargeable batteries, for example in building autonomous robot with arduino or wifi controlled robotic car. LiPo (Lithium Polymer) batteries have become a popular choice due to their high energy density and lightweight nature. However, charging LiPo batteries safely can be a challenge, as they require precise control of charging parameters to avoid safety hazards such as fire or explosion.

### The Solution: DIY LiPo Charger

The key to safely charging LiPo batteries lies in using dedicated LiPo-charging integrated circuits (ICs). One such IC is the MCP73831, designed specifically for charging LiPo cells.

Let's delve into the practical aspects of creating a DIY LiPo charger using this IC.

### Practical Example: Design and Components

Figure 8-6 illustrates a schematic for charging a LiPo battery using the MCP73831 IC. This simple yet effective design only requires two capacitors and a resistor in addition to the IC. Optionally, an LED and resistor (R2) can be included to indicate the charging status.

To determine the maximum charge current (Imax) for your LiPo cell, consult its datasheet and use the formula:

$I_{max}= \frac{1000}{R_1}$

For example, to charge at 500mA (the maximum allowed by the chip), set R1 to 2kÎ©.

### Ready-made Options and Safety Considerations

If designing your own charger seems daunting, fret not. Ready-made LiPo charge modules, such as the Adafruit 1905 and Sparkfun PRT-10217, are readily available. These modules typically utilize the MCP73831 IC and offer convenience without compromising safety.

Safety is paramount when dealing with LiPo batteries. Chargers like the MCP73831 help ensure safe and reliable charging by controlling parameters such as charge current. For added safety, consider incorporating a thermal fuse into the charging circuit.

### Discussion: LiPo Battery Safety and Alternatives

LiPo batteries have garnered attention due to their potential fire hazards if mishandled. Utilizing dedicated charging chips mitigates these risks, providing peace of mind for your electronic projects. Alternatively, if simplicity is preferred, NiMH or SLA batteries can serve as lower-tech alternatives.

It's essential to note that LiPo batteries cannot be safely charged in parallel, unlike NiMH or SLA batteries. Each cell must be charged independently using specialized hardware. If your project requires higher voltage than a single LiPo cell provides, employing a boost converter to generate the necessary voltage is advisable.

### Conclusion

Charging LiPo batteries doesn't have to be complicated or risky. With the right components and knowledge, you can create a DIY LiPo charger that ensures safe and reliable operation for your electronic projects. Whether you opt for a custom design or a ready-made module, prioritizing safety is key when working with LiPo batteries. So, dive in, experiment, and power your projects with confidence!