LiPo Batteries For Hardware Prototype Electronics

Selection of the power source for your product is one of the most important early decisions that you can make when developing a new hardware product with LiPo Batteries, You have three choices at your disposal: rechargeable LiPo batteries, replaceable/disposal batteries, or AC power.

Rechargeable LiPo batteries are the most common method of powering most modern consumer electronic products.
There are a variety of types of rechargeable lipo batteries, but two are most commonly used for consumer products: lithium ion or lithium polymer.

A lithium-ion battery uses a liquid electrolyte, whereas a lithium-polymer battery uses a gel-like polymer for the electrolyte. However, most lipo batteries that are labeled as lithium-polymer batteries are really lithium-ion polymer batteries.

A true lithium-polymer battery uses a polymer electrolyte, whereas a lithium-ion polymer battery uses a liquid electrolyte (just like a lithium-ion battery) but with a polymer casing.

Lithium-ion batteries are rigid, hard batteries typically used in laptops and larger products without a requirement to be ultra-thin. A single lithium-ion battery cell is commonly a little larger than a standard AA alkaline battery, but in most cases several of these cells are grouped together and encased in a plastic shell.

Lithium polymer batteries, on the other hand, are more flexible and can be made much thinner than a lithium ion battery.

Lithium polymer batteries cost about 10 to 20 percent more than a lithium ion battery, so for larger products it might make more sense to use a standard lithium-ion battery.
However, even for larger products, lithium-polymer batteries (which can be made into a variety of shapes) can allow you to pack more battery volume into your product. This allows you to increase your battery capacity/life without increasing your product size.

If your product is really small and thin then you’re probably going to want to go with a lithium polymer battery.

One significant disadvantage of rechargeable batteries is that they add significant cost to your product. The biggest cost is typically the battery itself.

Most products that use replaceable batteries don’t include the batteries themselves, so your product cost doesn’t include the cost of the batteries.

Also, you have to factor in the cost of the charger circuit itself. With lithium batteries you will also require a special device called a fuel gauge which monitors the charge level of the battery. These add a little additional cost.

Finally, you will need to include an external power charger of some sort (most commonly a USB charger) with your product.

All of this adds some additional cost and complexity. Luckily there are numerous integrated battery charger solutions available that take care of all the complicated stuff involved in charging a lithium battery.

One of the other issues with rechargeable batteries is they require additional safety certifications. Some of these certifications are UL1642, IEC61233, and UN 38.3.

A lot of the time you can buy stock lithium rechargeable batteries that are already pre-certified but your choices are going to be more limited. Most commercial products ultimately need to have a custom battery made just so the battery can use the maximum available space to increase the battery life and capacity.

Once you reach higher manufacturing volumes, you might want to switch to using a custom lithium battery to maximum your product’s battery life. At that time you will be forced to obtain the required certifications.

And finally, rechargeable lithium batteries have some serious safety issues. Most of you have seen stories about lithium batteries exploding in Samsung phones. Lithium batteries are potentially very dangerous.

So if you’re going to design one of these into your product, you need be aware of the safety concerns. Safety issues are why there are certifications required for lithium batteries.

Lithium batteries need a charger and fuel gauge chips, as well as protection circuitry. This circuit will prevent overcharging or shorting the battery which may cause it to explode or catch fire.

I recommend that you purchase lithium batteries that already have a protection printed circuit board built into the battery. That way, you don’t have to worry about any design issues causing your product to explode.

LiPo Batteries For Hardware Prototype: