Millions of Americans suffer from chronic pain every year, and rely on painkillers. However an alternative way of treating pain that has been gaining ground is through electrical stimulation. Since the human body uses the nervous system to communicate pain through electrical pulses, electricity can be used to treat pain and is more effective than pain medication for some people. Pacemakers and defibrillators, which save many lives, are examples of the use of electrical impulses to treat disease comprising a class of ‘electroceuticals’.
Transcutaneous Electrical Nerve Stimulation (TENS) therapy is a clinically-proven method for treating pain used by doctors and physical therapists all over the world. It works by delivering low-voltage electric pulses that stimulate the affected area, sending signals to the brain that block pain. Because these pulses move more quickly than the body’s natural pain signals, the perception of pain is blocked. In addition, TENS therapy may also promote the release of pain-relieving endorphins to provide longer lasting pain relief.
Historically, TENS devices are comprised of a small handheld device with two electrodes that are applied to the skin. The two electrodes, in combination with nerve fibers, form a circuit that allows current to flow through the area of the body between the electrodes. Although this method remains effective, advancements in technology have made TENS therapy available over the counter in small, reusable units that include a controller, battery, and adhesive electrode pads that conform to the area of the body that is being treated, such as the knee, shoulder, or back. This enables TENS therapy to be administered wirelessly and allows users to be mobile during treatment.
Integrating thin film batteries into these types of portable TENS applications will make the user experience even more convenient.
Improving TENS Therapy with a Thin Film Battery
Some of the ways that TENS therapy can be improved with the use of thin film batteries include:
Safety – Thin film batteries can be made bio-compatible and non-toxic, making them safe for use with medical devices that come in contact with the human body. Aqueous electrolyte battery chemistry allows flexibility while also providing a safer alternative to lithium-based batteries. Additionally, unlike the typical button batteries that are used with TENS devices, a thin film battery presents less risk of swallowing or other harm to small children.
Low-profile – Although the electrode pads that deliver TENS therapy are thin and conform to the body, the control unit will inevitably be larger and bulkier if a conventional coin battery is used. Using a thin film battery as part of a TENS patch that also conforms to the body in the same way as the electrode pad will further reduce the profile of the device, making it easier for users to wear it undetected. Unlike a coin-shaped battery that is rigid and inflexible, a thin film battery will bend with the user, so when the device is applied to a joint like a knee or elbow, range of motion is less limited. Likewise when used on the back, such a battery provides a more comfortable experience.
Cost – In addition to these benefits, thin film battery manufacturing can be effectively scaled up to provide a cost-effective solution that is appropriate for over-the-counter consumer applications. Keep in mind however that thin film batteries cannot match the price of coin cells on a volume scale and will typically be about 2 to 3 more expensive. Larger volumes will of course bring the price down. Both disposable and rechargeable options allow innovators to develop the type of TENS device that is most suitable for their target user.
Disposal/eco-friendliness – For TENS applications that enable single use in high volumes, disposal can be a problem with lithium coin cells, particularly in countries with stricter regulations. Even when lithium battery disposal is allowed, companies can capitalize on the opportunity to demonstrate corporate responsibility by choosing a more environmentally friendly option.
Battery technology continues to evolve, just as TENS therapy continues to become accessible to more and more users. Marrying the two technologies will open new doors for manufacturers and consumers alike.
If you are developing a TENS device or working on any other type of healthcare IOT application that could benefit from a thin film battery, consider working with Flexel for custom battery development.