Can A Brand New Li-Ion Battery Be Stored Indefinitely?

[Stefan Mikes]

I've just got a brand new Specialized Vado/Como battery. The battery has been freshly removed from the original box to fit the battery cover but never connected to the charger. There is no production date anywhere on the battery.
Can such a battery be safely stored for 1-2 years without intervention, and charged for the first time only when needed?

I ask this questions as some other people such as a friend of mine are buying new batteries for storage, so they could extend their e-bike lifetime, and start using the new battery only when the original one(s) health drops down to 70%.

I have found this information:

Lithium-ion batteries must be stored in a charged state, ideally 40 percent. Lithium batteries, including lithium coin cell batteries, have virtually no self-discharge below approximately 4.0V at 68°F (20°C). Rechargeable lithium-ion batteries, such as the 18650 battery, boast remarkable service life when stored at 3.7V—up to 10 years with nominal loss in capacity. A precise 40–50 percent SoC level for storage should not be a priority, but a more accurate reading is obtainable by resting the battery 90 minutes before taking the reading. Alternatively, you can overshoot the discharge voltage by 50mV or increase it by 50mV on charge.

Source

That could be true, as the battery maker never knows when the battery would be used for the first time. My Vado 2017 battery was charged for the first time 2 years post production. My extra Giant battery was "woken up of hibernation" by a salesman -- as he named that.

Does anyone know for sure? @Ravi Kempaiah, @tomjasz?

 

[tomjasz]

I've just got a brand new Specialized Vado/Como battery. The battery has been freshly removed from the original box to fit the battery cover but never connected to the charger. There is no production date anywhere on the battery.
Can such a battery be safely stored for 1-2 years without intervention, and charged for the first time only when needed?

I ask this questions as some other people such as a friend of mine are buying new batteries for storage, so they could extend their e-bike lifetime, and start using the new battery only when the original one(s) health drops down to 70%.

I have found this information:

Source

That could be true, as the battery maker never knows when the battery would be used for the first time. My Vado 2017 battery was charged for the first time 2 years post production. My extra Giant battery was "woken up of hibernation" by a salesman -- as he named that.

Does anyone know for sure? @Ravi Kempaiah, @tomjasz?

I ended up with more batteries than I needed and the 2-3 year old unused batteries batteries all brand name are sagging. All kept at 60F at 50% charge. Several thousand dollars of sagging packs. Sucks…

 

[HCooke]

The instructions that came with my Pedego say to charge the battery fully once a month.

 

[Handlebars]

I've just got a brand new Specialized Vado/Como battery. The battery has been freshly removed from the original box to fit the battery cover but never connected to the charger. There is no production date anywhere on the battery.
Can such a battery be safely stored for 1-2 years without intervention, and charged for the first time only when needed?

I ask this questions as some other people such as a friend of mine are buying new batteries for storage, so they could extend their e-bike lifetime, and start using the new battery only when the original one(s) health drops down to 70%.

I have found this information:

Source

That could be true, as the battery maker never knows when the battery would be used for the first time. My Vado 2017 battery was charged for the first time 2 years post production. My extra Giant battery was "woken up of hibernation" by a salesman -- as he named that.

Does anyone know for sure? @Ravi Kempaiah, @tomjasz?

Timely question, S. Lots of people are seeking to have battery security. I jumped in almost a year ago and haven't been using it because my original is still strong. I also wanted to have "camping distance" range.

 

[AHicks]

If the question is "will the brand new battery degrade while sitting on a shelf unused", the answer is yes. I would suggest you don't buy a battery you don't plan on using regularly....

 

[Mike TowpathTraveler]

Stefan, I've collected 3 500wh external Yamaha batteries to supplement the original 400wh on my Haibike. The 400 came with the bike, which is a model year 2016, placed in service in April, 2017. Purchased 2 500wh's fairly close to each other in time on 2018 and the 3rd 500wh was bought this past July, 2021.

Not a problem with any of them. I'll rotate batteries as I ride almost daily. And I admit to breaking the cardinal rule of battery storage by charging them to 100% and BMS shut off. The older 400 and one of the older 500's, when put into service after sitting for over a week or two, will lose about 5% of the full charge. Before riding, I just put it back on the charger and charge until the BMS shuts off. When on the bike, the display readout indicates a full, 100 percent charge; even on a battery that was celled in 2016. That to me, is amazing.

I can only speak as to how it worked for me and I could recommend that your friend place the new battery into service and just rotate the two batteries into their riding schedule. (I do not recommend they follow my peculiar way of charging the battery to 100% and then, letting it sit for weeks on end....!)

 

[Stefan Mikes]

First of all, thank you guys for your answers!

I ended up with more batteries than I needed and the 2-3 year old unused batteries batteries all brand name are sagging. All kept at 60F at 50% charge. Several thousand dollars of sagging packs. Sucks…

Tom, isn't it so that the proper SoC for a brand new battery should be 40%, or the voltage of 3.7 per each 18650 cell in series? Perhaps it is the 50% charge to be the culprit?

The instructions that came with my Pedego say to charge the battery fully once a month.

Ya, after the battery has been put in service.

The 400 came with the bike, which is a model year 2016, placed in service in April, 2017.

Mike, see what's interesting here: Your Haibike was manufactured in 2016) and the battery was placed in service only in 2017 with no side effects. The situation with my Vado was it was MY 2017 (and it was actually made in 2017!) but the battery got activated on October 31st, 2019 only. I received the second Vado battery mid-March 2020.

I have been charging both batteries to 100%, often discharging them down to 5%, and regularly rotating, with more intensive use of the newer battery. Now, the outcome has turned out to be unpredictable:

• Both batteries report about 90 full charges each only, which sounds strange taken into account how much I've ridden my Vado
• The older battery reports 95% health, while the newer one is only 90% good.

I thought that you could store an unused battery for a long time. I intend to keep my third battery at least until the Spring before I do anything with it. We'll see. I wonder if it makes sense to turn the new battery on and just measure the voltage?
-----------
There is a quite interesting matter with the internal and external batteries of my Vado SL. As the batteries can be discharged either individually or in parallel, I monitor them very closely since the e-bike was new (June 23rd, 2021), and take care of their equal number of charges. After 5 months and 2700 km ridden, here are the metrics for each battery:

• Main battery: 33 charges, 99% battery health
• Extender battery: 27 charges, 99% battery health.

 

[tomjasz]

Tom, isn't it so that the proper SoC for a brand new battery should be 40%, or the voltage of 3.7 per each 18650 cell in series? Perhaps it is the 50% charge to be the culprit?

That’s splitting hairs in my opinion.

 

[Stefan Mikes]

That’s splitting hairs in my opinion.

The article I quoted names 40% SoC or 3.7 V per cell for 18650. What was the original voltage of the batteries you mentioned?

 

[CATERHAM]

A lot depends on the battery chemistry.
I'm new to ebikes and am trying to determine the chemistry of the Samsung cells in the FREY bike I've recently ordered.
But as a Tesla owner the charging instructions are different for the Lithium Iron Phosphate (LFP) batteries vs the nickel based batteries such as NCA.
The LFP batteries are best charged to 100% SoC and kept at a full charge while in storage.
With nickel based batteries for maximum battery life the SoC in storage should be kept in the 40-50% range. In operation it is still best to keep the battery SoC in the 20-80% range and not charge to 100% unless the vehicle is going to be used right away.
I haven't gotten a clear answer on what battery chemistry is commonly used in ebike battery packs but I suspect they use nickel based cells for the higher power density. Assuming that is the case and since ebikes don't have the long range of Teslas, charging to 100% is the most practical thing to do dispite the fact it increases the rate of battery degradation.
Knowing that and just charging to 80-90% unless you're going to ride the bike immediately may be a good compromise.

 

[Stefan Mikes]

I have just activated a brand new Specialized battery, which was waiting in a cabinet for 6 months. 100% health.
It does not prove anything.

 

[6zfshdb]

As others have said, capacity loss will vary with age, battery type, charge routine and storage conditions.

In 2018, I bought 5 batteries for my 3 bikes. 3 are used regularly with approximately 200 charge cycles. They are 52V 15AH with Panasonic 18650 cells stored at 40 -50% in temps which vary between 55 and 75 degrees. Because I need the extra range, I charge to 100%, rather than 80%, just prior to use.

Measured with a bench test rig, the batteries which are in use have lost between 9 and 10% of capacity over 4 years while the new ones lost 4 - 5%. In my case, age does affect capacity somewhat. This is likely due to battery chemistry changes but it will take many years for that loss to render the battery unusable. At the present rate, I estimate they will outlive the bikes.

 

[tomjasz]

A lot depends on the battery chemistry.

Samsung 30Q 18650

I'm new to ebikes and am trying to determine the chemistry of the Samsung cells

INR/NCA

charging to 100% is the most practical thing to do dispite the fact it increases the rate of battery degradation.
Knowing that and just charging to 80-90%

Well, being new I would have expected you not to have developed ideas counter to the Lithium ion brain trust and acceted methodlogies. These aren't Tesla packs and charging to 80%-90% can DOUBLE pack life. ALL of Samsung and actually ALL 18650 cells have spec sheats. Just a Google away. Frey should be easy to get the cell version, but yes INR/NCA. Find the cell version and Bob's your uncle.

See @6zfshdb post!

 

[Gionnirocket]

Each manufacturer has a stated SOC and temp for storage and for my Samsung 18650's it was
STORAGE: 45.5V ~ 48V (mean 46.8V) or (55% - 68%)
That said I think you're much better off taking @Mike TowpathTraveler advise and just put it into rotation.

 

[harryS]

A lot depends on the battery chemistry.
I'm new to ebikes and am trying to determine the chemistry of the Samsung cells in the FREY bike I've recently ordered.
.....
I haven't gotten a clear answer on what battery chemistry is commonly used in ebike battery packs but I suspect they use nickel based cells for the higher power density.

Ebikes don't have the luxury of carrying 2x the capacity and only using half of it, so everyone uses the higher energy density cells. Occasionally, one or two bikes will be mentioned here that use LiFEPO4. Prodeco Tech, for example, used pouch cells in their rear rack batteries.

In my opinion, the 20%-80% recommendation is a bit overstated. If I charged to 80%, my range anxiety stress would ruin the day. I don't leave the house w/o a full charge,

 

[tomjasz]

I’m finding my 21700 50E pack is delivering incredible mileage. I used 7Ah to run around 15-20mph and get 2 times more mileage than my 18650 cell packs. Unexpected... no noticeable sag at 30F..

 

[rich c]

3 of my bikes were old model year. One was a demo, so had some charges, 2 of them had less than 2 miles on them. One of the packs is now 6 years old and performs good enough for me. I hate to state distances since Deacon Blues will question the validity of my post.

 

[Stefan Mikes]

I hate to state distances since Deacon Blues will question the validity of my post.

Show him your Strava

 

[Urbancowboy]

I ended up with more batteries than I needed and the 2-3 year old unused batteries batteries all brand name are sagging. All kept at 60F at 50% charge. Several thousand dollars of sagging packs. Sucks…

Good to know - thanks !
Cheers