Warning to Campagnolo EPS riders: Power Unit failures

[bikercr]

Don't apply the magnet strap when doing your first full charge (off-strap will prevent interface light from indicating the PU charge level). If the red light on the charger is steady red, that's good.

Flashing red (slow flash) on the interface indicates a very low initial PU charge. This is a unit that's sat in storage for over 6-12 months without a top-up charge and is likely somewhat damaged as a result. Even worse is no interface charge level light at all. Maybe Graeme can confirm this for us. You'll probably be able to get the PU up to "80-100%" with a 3 hour or more charge-up. But this may be just a "surface charge" (see next paragraph) that's really a permanently dead battery. However, even if it actually charges, it's not ideal and the lifespan and charge-retention properties of the power unit may be permanently impacted.

It's also possible that the PU will seem to rapidly take on a charge but will fail after one or two weak shifts (or none). What's happened in this case (and happened with the bad replacement PU I purchased to replace my first dead one), is a "surface charge" only. This is a power unit suffering from "undervolting"--the term used for a Li-ion battery that's sat at zero charge for too long and is now unrecoverable. This is the very condition that Campy likely won't warranty to the end-purchaser because the PU was IMPROPERLY STORED AND NOT ORIGINALLY DEFECTIVE WHEN IT LEFT THE FACTORY.

With the experience I've now had, I'd return your PU for a fresh one (at least a flashing green interface LED straight out of the box). The v4 batteries have been around since 2019. Going forward, with EPS no longer advertised by Campy and old stock sitting in storage in warehouses and bike shops, we riders have to watch out for broken or damaged PUs that were improperly stored and left to drain completely. Campy requires dealers to recharge unsold PUs every 3-6 months to avoid damage to the Li-ion battery and won't warranty to the end user damaged PUs fresh out of the box. This requires retailers to break the seal on new boxes, something I'm sure many are reluctant to do.

Because the end user can't determine on the outside of an unopened box how old the PU actually is, it's BUYER BEWARE. That's why I gave this post its initial heading. Good luck!

[bikercr]

There is extremely helpful information on the Velotech website regarding Campy EPS, charging, power units, warranty issues, etc.
Here's the link: https://www.velotech-cycling.ltd.uk/cam ... _faq.shtml

[bikercr]

Here's information on why Li-based batteries are damaged by very low or zero voltage. The author works for Lezyne.......

Let's clear up some misconceptions people have about LiIon and LiPoly batteries.

1) Almost all LiIon/LiPoly batteries have a protection chip inside them that no-longer lets the battery power devices when the Cells voltage reach a certain level. The most common cut-off voltage is 2.8V but can be much higher in certain applications.

2) Even after the protection chip cuts the cell off due to low voltage the CELL will continue to discharge at ~1-10uA. As a result eventually the CELL's voltage can reach 0V if not charged.

3) Unknown to most is that if the cell reaches 0V it CAN be recharged.
HOWEVER:
3a) Letting the cell reach 0V can permanently reduce the CELL's capacity.
3b) Most protection cells are not designed to let the CELL be recharged after the cell's voltage is below 0V.

4) Storing cells at around a 3.8V charge will achieve the longest lifetime and output of the battery.
4b) Storing at 3.8V also gives the cell plenty of headroom for self discharge. YES, a LiIon battery sitting by itself will discharge on its own.

5) Charging most LiIon batteries to 4.1V will give its longest lifetime (Non-Panasonic Cells).
5b) Charging most LiIon batteries to 4.21V will give the batteries the most output per charge but will decrease its lifetime (Non-Panasonic Cells).
5C) Panasonic Cells can be charged to 4.3V and is part of the reason they can have the highest output on the market.
5D) The same protection circuits that keep cells from over discharging also will prevent the cell from being over charged. Usual cutoff is 4.2V.

With all of the above being said, there are lots of considerations and tradeoffs in the design and use of LiIon and LiPoly batteries. Most batteries on the market will not let the cell be charged from 0V because it is the cheapest protection chip available.

Terry Cooke
5+ years developing commercial products with LiIon and LiPoly batteries.

[Butcher]

I don't have a steel bike but the only time I have ever used the magnetic strap is for a reset I had to do. Other than that, I have never used it for a good 8-10 years.

[glepore]

I don't have a steel bike but the only time I have ever used the magnetic strap is for a reset I had to do. Other than that, I have never used it for a good 8-10 years.

Good to know. I have 3 eps bikes, 2 v3 and one v1, and the ti and steel ones give me fits with the strap. I'll just keep them topped up and not worry about it. Hopefully Campy will continue to release v3 batteries for a while; the V2 bike is Chorus and I'll need to solder cable ends at some point to convert I suspect.

[bikercr]

Honorary Nobel prize to anyone that figures out the power unit manufacture-date code supposedly readable from the serial number on the box (and unit). With this Rosetta Stone, at least we can know how old a newly purchased power unit is without breaking the seal on the box. I bet there's lots of new ones for sale that are a year or more old, sitting uncharged and draining--either long term impaired or dead on arrival. It's a 10-digit code on the end of the box under the square 2d barcode. On the box containing the warranty-replaced v4 power unit (from Campy NA), that was about 50% charged fresh out of the factory-sealed box, it's 1700232339. I received this power unit in mid-January, 2024.

[Butcher]

If you really want to go down a very deep rabbit hole, research how lithium batteries work. It's darn near impossible to know if it is 50% charged by voltage. The BMS actually monitors the electrons as the pass in and out of the battery to know how much it's charged.

[saverin]

Relevant discussion in the comments on this video. Looks like V3 PU's are back in production (apologies if Graeme already mentioned that in this thread)

https://www.youtube.com/watch?v=9dEz6VOfeyQ

[AJS914]

Why is this a problem though in 2024?

I've worked in IT for 20+ years and I don't see this issue with laptop batteries. I've taken many an old, dead, sitting in the storeroom laptop and charged it up without a problem.

[bikercr]

Campy power units, like some other rechargeable batteries, are permanently kaput if left to drain down to zero for long enough. They will appear to take a charge, rather rapidly, but have no power to action more than a shift or two, then read zero charge (called a "surface charge"). I don't know if this results from damage to one or more cells or the way the internal computer chip is programmed. Some rechargeables, in order to prevent fires secondary to trying to charge a swollen battery, are shut down permanently by an internal safety chip.

The problem for the Campy rider is paying big money for a new v4 power unit in a factory sealed box, but finding that the battery is permanently dead or severely damaged upon first connecting it. This happened to me a few weeks ago. Campy will not warranty this to end users. It's due to improper storage before the battery was sold. These units need to be charged at least every few months in storage. Dealers, i presume, either don't know this or don't want to break the seal on a new box.

The chief East Coast USA Campy factory rep, a pro team mechanic, told me this by phone last week. I've sent my dead-on-arrival power unit to him for damage assessment (his location is Philadelphia, PA). When the store from which i purchased it gets his confirmation it's truly dead, they've promised to refund me.

All this could have been avoided if one of these occurred BEFORE I made the online purchase:
1) I confirmed with the seller that i would be immediately refunded for a dead one out of the box; or, 2) the manufacture date code was visible on the label of the box before i opened it.

I believe the PU was at least a year old, and probably older. It was completely dead on first connection to my interface (no lights at all) with a flashing red light on my charger box (bad). The retailer, an official Campy dealer, got the PU from another wholesaler and retailed it to me. That's where i think the unit sat in storage for a long time without being charged. The seller told me he didn't have it in stock for very long.

If we Campy riders knew how to interpret the manufacture date from the serial number on the box and PU, we could reject an older unit in a sealed box (never charged). For me, this was a multiple hundred dollars mistake.

[glepore]

Relevant discussion in the comments on this video. Looks like V3 PU's are back in production (apologies if Graeme already mentioned that in this thread)

https://www.youtube.com/watch?v=9dEz6VOfeyQ

Yes, but they're hard to get again. I ended up with one of the new ones last year when a guy purchased one not knowing it didn't work with his Chorus group. I tossed the box unfortunately but it had a V4 label but "for 11 speed" and works with the v3 interface. Looking online, only a couple retailers worldwide have them.

[bikercr]

Just for closure, got my full refund from the bike shop (Velo Mine) for the backup PU I bought that was dead out of the box. The bike shop received a replacement directly from Campy NA after they confirmed the one I bought was defective.

[glepore]

Its a shame, really, that both Shimano and Campy integrate the lithium batteries with a finite lifespan in a sealed package with the electronics necessary to make the system function. Instead of replacing a $100 power pack we're left with replacing a $500 power unit in Campy's case. And then, there is limited availabilty and questionable reliability. At least Shimano pu's are available for a reasonable price.

[Butcher]

There are many ways to make a system and all systems are finite. On paper, Lithium batteries will last longer than what we are going to use the item for. They do not like to be over/under charged. That is what the BMS is for. Sadly, there is nothing you can do about an under charged battery when it is in stock.

They could put the battery separately, but then you need additional items for that to work. Items that cost and weigh more. I do not understand the idea of wireless for shifting, but like what you have seen, the external batteries are hideous. With wires, they could have hid them. So many patents to be concerned about too.

I believe there is more of an issue with the dead units. Yes, a lithium battery will be NFG if undercharged but it should hold the charge for some time. Why is it getting so low in storage? Maybe because they were low when they were made? Maybe they were not charged completely before they were put in a box? Maybe the electronics turn on while in storage? Maybe the BMS settings are too low which causes the batteries to get to that state? We consumers will never know.

Good to know that the problem got resolved, sad to think you have to go through all those hoops to get the system to work for you.

[bikercr]

Thank you for that sentiment! It's difficult to be a Campagnolo customer right now in the States. Campy North America refuses to accept defective merchandise directly from the end-user for warranty replacement. Instead, we have to find a bike shop willing to return the item to Campy on our behalf. This often involves paying inflated handling and shipping charges, and dealing with shops that don't stock Campy equipment and sometimes don't know anything current about EPS and even mechanical groups. Because most local shops don't carry Campagnolo any more (just Shimano and SRAM), we have to mail order from companies that may or may not support the end-user with problems after the sale.

The good thing here is that we can usually reach a human being with a simple phone call--either the Campagnolo West coast or East coast rep (Steven Berg or Marzhel Pinto). Marzhel was very helpful and considerate regarding the problems I described above. I was also lucky to have Steve from Velo Mine (from which I mail-ordered) help me out with returning (to Marzhel) and getting refunded for the replacment PU I bought. I really love Campagnolo equipment and have raced and ridden it for the past 30 years or so. But warranty issues are a real pain and may dissuade me from future investments in new groupos.