Advice for choosing Rechargeable Lithium Batteries to be used in a Medical Device

[mr.mike]

Hi There,

Can someone out there provide some advice on requirements for a battery to be used in a medical device? Here are the details:

Battery Type: Lithium, rechargable, primary power-source, non-replaceable
Device Type: Non-measuring, non-implantable, Class II
Market: Want to keep as broad as possible, but at minimum US, Canada and EU

I'm a bit overwhelmed by the number of battery-related standards (see the following thread: https://elsmar.com/Forums/showthread.php?t=44775&highlight=lithium)

We've sourced out some batteries that meet UL1642, UN38.3 & RoHS.

However, I believe IEC-62133 now replaced UL1642 (see https://www.fi.sgs.com/battery-standard-iec-62133-replaces-the-ul-standard-within-the-iecee-cb-scheme-fi.htm?selen=1&viewid=5761). So does this mean we'd have to get a NRTL to re-test these batteries to the IEC standard?

Also, I'm not even sure these standards are totally necessary given the nature of the device, target market, and risk-classification.

Any advice would be greatly appreciated...
Thanks in advance,
MM.

 

[somashekar]

We've sourced out some batteries that meet UL1642, UN38.3 & RoHS.

Do they carry these marks and from a reputed NRTL ?

So does this mean we'd have to get a NRTL to re-test these batteries to the IEC standard?

Not the batteries, but your device with the battery included and which is based on your justification for the selection (include alternate batteries make as well for business reasons) and get your device approved with such batteries as well.

 

[Pads38]

The battery requirement in 60601 is being updated in the forthcoming amendment.

For secondary (ie rechargable) lithium batteries the standard it calls is IEC 62133.

(Note: PRIMARY battery = non-rechargable; SECONDARY = rechargable so be careful how you describe your battery).

According to here -
https://www.intertek.com/energy-storage/battery-safety/iec-62133/
IEC 62133 is replacing UL 1642.

 

[Pads38]

Mike - I followed your link and I think the answer is there:

From October 26, 2010 additional tests must be carried out on CB certified batteries tested in accordance with UL 1642 to ensure that they comply with standard IEC 62133.

Although I would hope that a competent battery supplier would be "on the case" and would be seeking the updated certification as soon as possible.

 

[mr.mike]

Well, now that we are passed the May 1st, 2012 deadline it appears that all lithium-ion batteries must be fully tested to IEC 62133 for CB Certification.

Here is the link again: https://www.intertek.com/energy-storage/battery-safety/iec-62133/

This is unfortunate, as anyone in the midst of development at this point will be hard-pressed to find a supplier that is on-the-ball enough to have their batteries tested to IEC 62133 (most still have the old UL or UL+gap-testing).

...and the cost to have batteries tested yourself is huge! (sigh) what is a small developer to do?

BUT: if you're NOT aiming for CB certification (e.g. marketing only in the US) then this new regulation does not apply, correct?

On that note, does anyone know if the FDA has any guidance/regulations when it comes to lithium-ion batteries in medical devices? I've gone through the CFR 21, but can't seem to find any such info.

 

[Peter Selvey]

In regards to IEC 60601-1:2005 which refers to some new IEC standards directly (not only for Li-ion batteries, but also for flammability), it is possible to invoke the equivalent safety clause (4.5) as a temporary measure while the component industry gets up to speed. In other words, under risk management, indicate that UL recognition provides an equivalent level of safety to compliance with IEC standards.

Of course, responsibility for this decision rests with the manufacturer, and acceptance (e.g. for NRTL, CB scheme, third party testing) will depend on the certification body, but I know of cases where this has been used and accepted at least for flammability.

One issue with Li-ion batteries is that one of the key safety aspects (explosion due to overcharging) is not actually addressed by any of the standards (UL or IEC). Instead it seems that manufacturers are for once ahead of standards and include special protection ICs inside the pack. Certification agencies don't seem to be able to get their head around the use of an IC for protection, so the issue kind of gets ignored in a fuzzy ducking of responsibility (the battery testers say the end product must have overvoltage protection, while end product testers don't know what to check, and in any case the protection has to be in the pack, not external).

So I would recommend that even if the pack has UL or IEC recognition, check with the supplier to make sure the protection IC is fitted.

 

[SteveK]

As an additional thing to consider is air transport of medical (or other items) with lithium batteries (sorry if this is covered elsewhere) - if that is a planned route of supply/shipment.

See:

(broken link removed)

The reason I raise this is that initially we had issues air freighting a MD with just NiMH batteries - Li types are a whole different ballpark.

Steve

 

[mylene]

Hello,
for the Canadian market, i am faced with a big question that no one seems to be able to answer. I have a battery LI-ON IEC62133 certified. We are testing our device with that battery for 60601-1. Do I need to have the UL2054 over and above all this to access the market? i.e. Do I need the UL2054 to pass the 60601-1 certification? If not, do I still need to be tested against UL2054 in order to have a safety mark?
By the way, does medical device that has the 60601-1 still need to have a safety mark for canada or europe? I thought this was only for USA?
Tks!

 

[Peter Selvey]

If you are strictly looking at Canada, IEC62133 should be OK for the battery.

For Health Canada, IEC 60601-1 (and IEC based standards) are generally OK, and also no product certification is required.

Local state electrical code can additionally require a SCC accredited mark. The "object" of the SCC code is limited to electrical shock and fire, but this would still reasonably include Li-ion batteries.

The SCC uses CSA standards. But, the CSA standard has no special mention of Li-ion batteries, so IEC62133 should be OK.

However, most manufacturers apply for a combined agency mark to cover both US and Canada (NRTL and SCC mark). It is most efficient this way.

If so, you will also pull up UL 60601-1, and hence UL 2054 for the Li-ion battery.

Also, most agencies are so used to handling a combined mark that if you did only ask for Canada (SCC) they could easily forget the reason why UL 2054 is called up, and simply ask for it anyway. If so, ask the agency to show the exact clause which requires UL 2054 (as opposed to IEC62133).

 

[mylene]

Hi Peter,
thank you for your reply. You are totally right. This is exactly what is happening. The accredited lab is do used to request UL 2054 (for North America; combined Canada and USA). When I told him that we didn't want to have access to the US, he didn't know if still needed the UL2054. Where can I get this information myself instead of relying on them? Is it directly inside the standard 60601-1? I doubt because the standard doesn't even quote the 62133...
Tks,
Mylene