automated 'storage mode'?

is there a charger that can put a li-ion battery in ‘storage mode’?

what i mean is, charge it up to 40-50% capacity and then stop?

supposedly they last longer this way, if you don;t plan to use them for a while

wle

SkyRC mc3000 can be programmed to terminate at desired voltage level, I believe.

Opus BT-3100 has has an internal switch to charge to 3.7 volts. Just have to remove a bit of plastic to make the switch accessible.

In case the (correct) information in previous post looks a but too much like shorthand:
on CPF member “realista” published a picture of this switch. I hope he does not mind me posting it here.

Standard voltage of the BT-C3100 is 4.2V but can be altered in 4.35V or 3.7V (for charging LifePo4 batteries?). There is a switch on the “motherboard”, but to get there you have to open up the charger from the underside. “realista” shows us he has overcome this nuisance by making a hole in the underside of the charger.

HKJ has mentioned the presence of the switch in his review, but he wrote he did not look into it any further.

ISDT SC-608 can do it

The newly-released XTar VC4S appears to have a capacity test and a storage mode.

I have only seen 1 Youtube review of this new model (it’s not yet listed on Xtar’s website, although Xtar has been announcing it on their FB page).

I hope to see more reviews of the Xtar VC4S soon. (it uses micro-USB QC3.0 or QC2.0 9v/5v input).

In other news, Xtar has also announced an upgrade to the Xtar VP4 Dragon Plus, not sure what is upgraded on the newly revised model though (no specs yet, and I haven’t found a review of it). I seem to recall Xtar has already given a name to it, something like Xtar VP4 Dragon Pro or something… Would also be interested to see that unit reviewed (maybe it will also have a storage mode)

I have the BT-C3100, made the small hole in the base and use the switch. It does work.

https://youtu.be/wPF9LoOvYY0 - this is the only review of the VS4S.
There is no word about capacity test by discharge and storage mode. I have exactly the same charging of the VC2S for 2 slots and she also doesn’t have capasity test and storage mode.

Just curious about the storage voltage. Is that accurate about Li-ions keep better at a lower voltage? When I get mine I charge them then store them. I know over time they will deplete ever so slightly. I have some that have sat for a year and are at 3.9 or so.

For long term storage, full charge is a bad thing. That is why laptop batteries die prematurely if you constantly have the laptop plugged in to AC power and battery stays at 100%.

Keep them at around 50% charge level for long term storage. Some sources suggest even lower: 40%.

To get an “automated ‘storage mode’, any charging with LiFePO4 support will work. After inserting your 4.2V or 4.35V cell, select the 3.6V charging mode (LiFePO4) and your cell will charge to about 50%.

Your choice Liitokala Lii-100 :laughing:

[quote=Pete7874]

Absolutely. Heat and storage at full charge are not good for longevity. Mine are stored at 50% and in the fridge. I may start using 40%.
Lots of really good info here:

From some university research, there is a plateau effect, where you see only gradual improvements in shelf-life as you decrease from 100% state of charge to about 60, then there is a significant decrease in aging at 60, followed by a return to the trend of continue of gradual improvement.

Temperature also matters. Storing batteries in a hot car could easily halve the useful shelf life compared to normal room temperature.

However, you also don’t want to store them so low that any parasitic drain or self-discharge could reduce the voltage so far permanent damage occurs.

So 40-60% is indeed a very good choice. If you want to go the extra mile, aviation safety research determined that below 30% state of charge, thermal runaways are much less likely to propogate, release less energy, and have lower peak temperatures than at higher states of charge.

I believe that the airlines are going to specify that batteries be shipped at 30% rather than 50%.