Three medical battery experts divulge all

The medical device battery sector is on a major growth trajectory, as evidenced by a new Lucintel report valuing it at $2.2 billion by 2024. Three individuals with a vested interest in this growth include Dan McMartin, Interstate Batteries’ supplier quality engineer manager/ISO management representative; Vivek Bhatt, GE Healthcare’s chief technology officer, Clinical Care Solutions; and Vionnta Rivers, AlphaSource’s chief commercial officer.

Below, McMartin, Bhatt, and Rivers discuss what’s propelling growth in the medical equipment battery market and reveal what pitfalls to avoid when purchasing medical batteries.

24×7 Magazine: What’s new in the medical equipment battery sector?

Vionnta Rivers: Lithium-ion batteries are being used everywhere—from cell phones, to automobiles, laptops, and medical devices. The strain on supply has created shortages and increased costs. Per Science Daily, new chemistries are being developed, such as sodium-ion, to use as a possible replacement. As with anything new, however, where there may be gains in one area, there may be losses in others. Specifically, sodium-ion batteries have shorter lifetimes than lithium-ion ones. But once this hurdle is crossed, we may see new batteries developed that are cheaper and are made with more abundant materials.

Vivek Bhatt:The long-term goal for any battery should be to last the life of the device. The need for longer shelf life and higher capacity continues to increase for primary cells while demand for longer cycle and float lives are climbing for secondary (rechargeable) batteries. Additionally, for many applications, energy density improvements are needed both in mass and volume. And as the medical equipment market expands to global areas, which have poor AC power quality, batteries are increasingly looked upon to provide the stored energy necessary to ride through short-term power outages.

Dan McMartin: OEMs are introducing firmware updates to address issues like overheating and potential equipment damage in batteries that are used beyond the recommended service life. These updates trigger the devices to refuse to use batteries that exceed a predetermined number of charges/discharges. Techs who are implementing those updates to devices, such as infusion pumps, will need to coordinate a supply of compatible batteries to avoid downtime.

24×7: What are the biggest dos and don’ts when purchasing medical equipment batteries?

McMartin: Do look for suppliers with a quality management process certified to ISO 13485. This ensures strict manufacturing quality, proper warehousing control, and an active quality management system.

Don’t buy OEM or aftermarket batteries from any seller that is not FDA-registered. These batteries may have been previously used, stored in unknown warehouse conditions, or built with old/recycled sub cells. Ensure your battery supplier is FDA-registered by visiting the agency’s website, which is accessible here.

RiversFirst and foremost, purchase your medical batteries from a trusted source. FDA registration and ISO 13485:2016 certification will give you an indication that the source has been vetted by an independent, outside organization that has you—the end-user—in mind.

Bhatt: It’s important to purchase batteries that are qualified to relevant industry standards. For example, for lithium cell-based batteries, the UL1642 Standard for Lithium Batteries could be considered as a requirement, and for lead-acid chemistries, the IEC60896 Standard for Stationary Lead Acid Batteries may be recommended.

It’s also important to understand where a battery is currently manufactured and qualify that factory through a robust audit process. The date of manufacturing should be labeled on the battery or its shipping package and requirements should be considered to limit the maximum age of batteries purchased. For secondary batteries, the date of last charge can also be a specific labeling requirement since these types of batteries are often subject to loss of charge, over time, and can be damaged if not recharged according to manufacturer recommendations.

24×7: How have medical equipment batteries evolved in recent years and how do you expect them to evolve even more in the future?

Bhatt: Battery-assembly technology continues to evolve by adding electronics to provide safety and performance improvements. Circuitry to provide safety disconnect and charge equalization of cells has been available for several years. Additional smarter circuitry is becoming available to manage aspects, such as internal temperature, tracking of charge/discharge history, and providing accurate state-of-charge status.

The integration of artificial intelligence with internal battery management electronics will continue to evolve to extend battery life and provide notice of needed replacement to increase medical device reliability. Also, internal electronics can communicate authentication information to help reduce the chance of counterfeit or unauthorized battery replacements in the field.

McMartin: We’re seeing more and more devices move from sealed lead acid/nickel-cadmium/nickel-metal hydride battery chemistry to lithium-ion. These new batteries tolerate deep-discharge and poor charging habits much better than the older chemistries do. However, failure to follow strict manufacturing processes could result in a negative customer experience, which could ultimately lead to equipment damage or injury. This is even more reason to ensure your battery supplier is certified to ISO 13485:2016 and FDA-registered.

These lithium-ion batteries frequently have on-board chips that communicate the battery’s charging history and health back to the host medical device. While this does offer some advantages to the user, it also adds a level of complexity, which could mean additional management work, as well as the potential to create issues with software updates.

Rivers: Medical batteries have gotten smaller, more powerful, and charge faster. I would expect that to continue. Advances in battery design will allow for better monitoring of battery life and capacity.

24×7: What are the top safety considerations regarding medical equipment batteries?

Rivers: If you feel that a battery is damaged or is overheating, swollen, or is not behaving normally, discontinue use and contact the battery manufacturer for disposal instructions.

McMartin: The FDA has several recommendations for battery safety:

  • Don’t use batteries beyond their rated duty life. The medical device service manual generally states a replacement schedule recommendation.
  • Always fully charge a battery before first use since many batteries are not shipped at full capacity.
  • Routinely inspect sealed lead acid batteries for swelling or leaking.
  • Don’t deplete batteries completely before recharging. Whenever possible, plug the medical device into the main power. After all, complete discharges can shorten battery life and reduce capacity.

Bhatt: 

Most secondary batteries in medical equipment have very low internal resistance and should be protected from any short circuit condition with over current safety devices. Care should be taken when replacing any batteries of this type to avoid accidental high-current discharge by electrode contact with tools or other metallic items. Equipment should be turned off with minimal battery current flowing during any replacement procedures.

For older equipment that lacks smart cell-balancing technology, it’s important to check and replace battery units that are outside of manufacturer recommendations for series applications. Cell imbalance can shorten the life of batteries and increase the operating temperature of batteries during charging cycles. Every effort should also be made to recycle batteries containing harmful materials.

24×7: From a maintenance and handling perspective, what should HTM professionals know about medical equipment batteries and why?

Bhatt: Battery technology changes almost daily. There are many types of battery technologies for different equipment applications, different storage conditions, charging solutions, and different hazards based on battery technology. HTM professionals need to stay educated about the proper use, storage, charging, and disposal of batteries.

Rivers: Follow the charging instructions as described in the host device’s Instructions for Use. Batteries left in the devices and improperly charged or cycled can reduce their effectiveness and possibly cause a patient incident. Also, establish a preventive maintenance schedule for cycling the batteries and for switching them out on a regular basis.

McMartin: HTM professionals should never wait for a battery to fail to replace it. Batteries can fail in unpredictable ways, including overheating and swelling, which can damage medical equipment. Batteries should be replaced on a planned maintenance schedule. HTM professionals should communicate with their provider three to six months prior to the planned maintenance, so they have a fresh inventory and prevent back-orders.

24×7: What else do you want to tell 24×7 Magazine readers about medical equipment batteries?

McMartin: Aligning your planned maintenance schedule with a reliable supplier can help you avoid costly downtime. In addition, you should also question if the batteries are “fresh.” After all, a battery sitting in inventory for nine to 10 months will have a shorter duty life than a factory-fresh battery, which could lead to unexpected failure.

Bhatt: Battery quality and management is critical to avoid device failure due to premature battery capacity loss. However, devices and smart batteries should recognize capacity loss and warn the user or service agent before the capacity drops to critical low levels, which could result in a device that is unable to complete patient procedures or is rendered unavailable.

Batteries may be considered commodity devices in other industries, but, when used as part of a medical device, a battery must have high quality and be reliable when called upon; otherwise, it risks compromising the operation of the device. This entails creating a set of purchasing requirements and verifying that the proposed battery meets those requirements over the production life of the medical device.