Hearing aids are now a must-have for hearing impaired patients. Hearing aid batteries are an important factor in ensuring that hearing aid functions are continuously available. So what types of hearing aid batteries are there? What kind of battery is better? So today I will help you answer these questions...
What is a rechargeable battery?
A rechargeable battery is a rechargeable battery with a limited number of charge cycles and is used with a charger. The market generally sells No5 and No7 but also has No.1. The advantages of rechargeable batteries are economical, environmentally friendly and fully electric, suitable for high-power, long-term use of electrical appliances. The voltage of the rechargeable battery is lower than the voltage of the same type of disposable battery. The AA battery (charge No. 5) is 1.2 volts, and the 9V rechargeable battery is actually 8.4 volts. The average number of charges can now be around 1000.
Type of rechargeable battery
The rechargeable hearing aid batteries on the market are now divided into three categories, 1. Nickel hydrogen, 2. Silver zinc, 3. Lithium Ion Battery
NiMH hearing aid batteries have been produced for decades. However, such batteries have a number of disadvantages. Due to the limited battery capacity and the inability to meet the requirements of continuous battery life, these batteries do not allow hearing aids to work throughout the day. There are also a small number of charging times, and the number of cycles does not exceed 300. Therefore, its service life cannot last for a whole year.
Silver-zinc batteries are the most dynamic water-based batteries. So far, zinc-silver batteries have experienced more than 100 years of development. The theoretical energy density of zinc-silver battery is 300W·h / kg, 1400W·h / dm 3 , and the actual energy density is 40~110W·h / kg, 116~320W·h. / dm 3. The current research direction of zinc-silver batteries is to further improve the characteristics of zinc-silver batteries, and the bipolar design increases the discharge density of active materials.
Lithium-ion batteries offer more acceptable operating times, and they can be recharged so they do not need to be replaced frequently. However, there is currently no single-chip battery charging solution on the market. A typical hearing aid electronic circuit is operated directly from a single-cell zinc-air battery, while a lithium-ion battery has an output voltage that is approximately three times that of a zinc-air battery. Therefore, lithium ion battery based solutions require a battery charger and a buck regulator to provide the correct voltage to power the hearing aid ASIC chip.
Main factors affecting battery performance
Advanced features; wireless steam; amplification and battery current consumption
1. Advanced features
Modern hearing aids use many advanced features to provide louder, cleaner and more comfortable sound. Technologies such as noise suppression and feedback cancellation continuously monitor and process sound on the onboard computer. These active processes increase power consumption and result in higher battery consumption. These features are not only different between hearing aids, but also for hearing aid users. For example, a heavier hearing loss person may require more feedback cancellation than a person with less hearing loss, and may have more requirements for the battery and a shorter battery life.
2. Wireless transmission
Wireless transmission is another technology that leads to increased power consumption. Every time you transfer audio from a smartphone, TV, iPad or other wireless accessory, it consumes a lot of energy. Wireless streaming also occurs when your left and right hearing aids talk to each other to exchange audio or data. Many hearing aids maintain a constant wireless connection to provide more comfort and benefits in noisy environments. The more wireless transmissions, the more power the battery consumes.
3. Amplification
Battery performance is also affected by the amount of amplification provided by the hearing aid. When you increase the volume of the hearing aid, the hearing aid will discharge the battery at a slightly faster rate. For those with more severe hearing loss, more amplification is needed to provide enough volume, which also means more power consumption. In addition, if the hearing loss of one ear is heavier than the other, the battery life of the side ear may be shortened.
4. Battery current consumption
Battery current consumption refers to the speed at which the hearing aid consumes power from the battery. Hearing aid manufacturers typically publish power consumption data for each of the new hearing aids they produce. When the manufacturer measures current consumption, the hearing aid will enter "test mode", which disables advanced features and wireless connectivity. Therefore, manufacturers' current consumer specifications often underestimate the real battery consumption in real-world applications.
How to maintain the hearing aid battery.