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 are the types of hearing aid batteries? 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 No. 5 and No. 7, but also has No. 1. The benefits 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 that 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. Now the average number of times of charging can be around 1000 times.
Type of rechargeable battery
The rechargeable hearing aid batteries on the market are now divided into three categories, 1. Nickel metal hydride, 2. Silver-zinc, 3. Lithium-ion
NiMH hearing aid batteries have been in production for decades. However, this battery has many disadvantages. Due to the limited capacity of the battery and the inability to meet the requirements of continuous battery life, these batteries have no way to make the hearing aid work all day. There is also a small number of times of charging, and the number of cycles is not more than 300 times. Therefore, its service life cannot last for a whole year.
Silver-zinc batteries are the most energetic aqueous batteries. So far, zinc-silver batteries have undergone more than 100 years of development. The theoretical energy density of zinc-silver batteries 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 specific characteristics of zinc-silver batteries, bipolar design and increase the discharge density of active materials.
Lithium-ion batteries provide a more acceptable operating time, plus 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 operates 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 steaming; amplification and battery current consumption
1. Advanced features
Modern hearing aids use many advanced features to provide louder, cleaner and more comfortable sound. Techniques 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 differ not only between hearing aids, but also by 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 drain the battery at a slightly faster rate. For those with more severe hearing loss, more amplification is needed to provide sufficient volume, which also means more power consumption. In addition, if the hearing loss of one ear is heavier than the other, the battery life on that side 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 usually publish data on the power consumption of each new hearing aid 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 consumption specifications often underestimate the true battery consumption in real-world applications.
How to maintain the hearing aid battery
1. Rechargeable hearing aids should be recharged every night to maximize battery life. If you charge the battery every other night, this will not help extend battery life and can cause problems. Silver-zinc chemistry must have the opportunity to charge to full load every night to get the best performance from the battery.
2. Leave the hearing aid in the charger when not in use. The charger does not overcharge the hearing aid and ensures that the battery remains fully charged. Silver-zinc batteries do not have the same memory as older rechargeable batteries. To ensure optimal performance, you need to put them in the charger when not in use.
3. To ensure that your hearing aids are properly charged, it is important to dry and clean the hearing aids and chargers before charging. Use a soft tissue to remove moisture or debris from the hearing aid and charger contacts. The soft brush included with the hearing aid can also be used to remove debris from the charging hole.
4. Short-term storage - If you do not plan to wear a hearing aid within a few days, simply place the hearing aid in the charger.
Long-term storage - If you plan to use a hearing aid for a long time, it is best to remove the rechargeable battery from the hearing aid and store it separately.