Charger with storage profile?

Batteries, Chargers, and Battery Management Systems.
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raylo32   10 W

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Charger with storage profile?

Post by raylo32 » Feb 19 2019 7:30am

I have a couple of RC smart chargers for my planes and quadcopters that charge up to 6S and they have profiles to take a Li battery to storage condition by either charging or bleeding off charge to get to the storage voltage. It is good for bringing used batteries up to storage and for bleeding unused or underused batteries down to storage. Is there a 52V e-bike charger that can do this?

Hayds13   10 mW

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Re: Charger with storage profile?

Post by Hayds13 » Feb 27 2019 4:17am

eBike chargers generally don't have a "storage charger" option like RC Chargers do.

Some chargers have 80% charge settings...which is a little above storage charger voltage.

Grin's Cycle Satiator charger will allow you to create a profile that is the same as a storage charge. You'll just need to discharge the battery below the storage charge point first, then charge up to the storage voltage.

You could use a multimeter to check battery voltage when charging/discharging to determine if that battery is at storage charge.

Another option is to build your own charger with a power supply and boost converter.

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dogman dan   100 GW

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Re: Charger with storage profile?

Post by dogman dan » Feb 27 2019 7:25am

A few vendors sell bulk chargers that have a 50% 90% 100% setting. Em3ev is one. Not sure if he still has those or not.

But storing a bms equipped battery at 50% for long can result in the bms draining a few cells to 0v, ruining the pack. Monthly recharge to 90% or 100% best for a battery with bms, unless you can unplug the bms easily.

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amberwolf   100 GW

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Re: Charger with storage profile?

Post by amberwolf » Feb 27 2019 2:36pm

raylo32 wrote:
Feb 19 2019 7:30am
It is good for bringing used batteries up to storage and for bleeding unused or underused batteries down to storage. Is there a 52V e-bike charger that can do this?
Cycle Satiator, from http://ebikes.ca will charge up to whatever point you want, though it has no discharge function, so as noted above you'd need to discharge it yourself (by riding, for instance) first.

You can create profiles for just about anything; I don't recall if it comes preloaded with such a profile, but it would be easy enough to make even with just the on-screen buttons. THere is also a cable available to connect it to your USB port on a computer and use their free software to configure it, and to save existing presets and upload new ones.

Also as noted above, you need to keep an eye on the pack if it has a BMS, as the BMS will drain the pack constantly all the time it is attached. Most can't simply be unplugged from the cells completely (the main plus and minus are usually soldered to the BMS board)

raylo32   10 W

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Re: Charger with storage profile?

Post by raylo32 » Feb 28 2019 9:30am

Thanks for the discussion folks. I also had a chat with Grin Tech and came to basically the same conclusion. Looks like a good strategy to use for longer periods of storage is to periodically put the battery on the charger approaching or up to 85% to get the BMS to equalize the cells. This was also a big discussion with Makita tool batteries whose BMS would in storage drain particular cell(s) until the balance was so far off the charger would refuse it. This was causing many premature battery failures for many folks. I use a similar strategy with those, just topping unused batteries up for 5 or 10 minutes every several months or so and I have never had a battery failure, some of which are at least 5 years old.

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flippy   100 kW

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Re: Charger with storage profile?

Post by flippy » Feb 28 2019 9:55am

or just get a cheap charger from aliexpress targed at a votage roughly aimed at 50% capacity and just leave it on until you need it again the charger will keep it on the voltage set. i use this trick for larger packs with a dual charger system (one 800W charger and another 100W one) and the low power charger stops are 3.9V per cel. it also keeps the heater on 15c so the battery remains warm at all times.
Lithium beats liquid dinosaurs.

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