Yes, a very good thing. 
By adjusting the settings one can be used as a backup for the other and/or a way to adjust the charge level to increase cell life.
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How much of a difference does stopping charge at 4.1v/cell make in the life of the pack?
I’ve seen research results that, under ideal circumstances, results in about a doubling of the cycle life. But those tests were done at low charge and discharge rates with no other abuse (vibration, high or low temps, etc.) on new cells.
I doubt anyone would get anywhere near those kind of results under the brutal conditions esk8 packs are subjected to. But it would probably result in a noticeable increase in cycle life.
It comes at the expense of range though. Undercharging the pack to 4.1V per cell could take 10% or more off your range.
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The taper current value has an effect too.
If you charge at 2A per cell and stop at a typical rate, 200mA, then you’ll get a ”typical” charge. If you let the charge go until the current drops to 20mA then you’ll get a bit more charge (and range) but less cycle life. If you stop the charge at 1A then you’ll get less charge into the cells but the voltage will settle a bit lower and you will get more cycle life.
Both the charge voltage and taper/termination current settings can be adjusted to affect cycle life and charge time.
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Would your BMS have a setting for this? Maybe a mode for people with massive packs that want to increase cycle life for casual rides/ to retain resale value?
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Some do, some don’t. Any BMS I design lets you adjust the charge voltage and taper current values. You’d have to check whether the particular BMS you are interested in has that feature or not.
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I use a drok cc/cv with a psu. It’s adjustable and it’s nice to be able to see when your pack is full and trickling at 0.1a I assume that means it’s still balancing a bit. I have never seen it less than that though for amps.
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Most llt and Daly do this. Well at least the ones I use in my builds do.
I’ve broken every cheap bulk power supply I’ve ever gotten. Meanwell or nothing for me going forward. Get the waterproof fan-less one with adjustable voltage n current! And wire in a wattmeter. You have to attach a wattmeter and it’s the difference between knowing nothing and possibly blowing up and knowing everything
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Many supplies/chargers/devices are not very accurate at low current levels and will show 0.1A even though much less (even zero) current is flowing. There might be around 100mA flowing but there is a good chance that there isn’t.
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Hey can you elaborate on float / trickle charging?
I own 2 of these enertion chargers and also found the they only output 3a instead of the advertised 4.
Enlight me
Edit: maybe I should just read the thread
It doesn’t there is only a few main parts of charging li-ion we really need to keep in mined
Bulk charging with cc cv
Balancing (if it’s a charge only balancing)
Charge termination
Temp monstrance
In esk8
Monatring temp in e skate community is mainly ignored
Balancing is expected to be done by a charge only BMS
Very few of the charges and bms used terminate the charge
So how dose @Battery_Mooch justified that terminating the charge is the part of the PSU but not the cell balancing?
If we talking about a charger in my opinion unless it a hobby charger with balance leads and temp Sencers it’s not officially a charger. All the bricks are PSU’s no matter if thay terminate or not. You can go to the extreme of mounting the PSU in the board and just call the ac electric lead in to the board the charger. That’s what some electric bikes do
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Because that is part of my definition of what a charger can be. Your definition says that a “charger” must have balancing. My definition says a BMS can do that (r no balancing at all) and the power supply can still be called a charger. Each of us is free to define a charger any way we want, there is no one “correct” answer.
Millions of “chargers” exist to only bulk charge a pack, leaving the balancing to the BMS. This includes every laptop, phone, tablet, and millions of other commercial/industrial devices. Only a tiny, tiny percentage of the packs out there are charged with balancing chargers (since the packs have no BMS and require separate balancing).
This can be looked at as a disadvantage just as much as it can be looked at as an advantage.
Your balancing chargers are also just power supplies. They have added features added on but they’re still just power supplies, same as non-balancing chargers.
I understand you though and completely respect that you feel that a power supply cannot be called a charger unless it balances too.
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i think thats generally how people make the split
There should be. Ambiguity leads to fires and death and frustration
99.99999% of all the devices called a “charger” do not balance though. It is only within the (relatively) small hobbiest/enthusiast communities that we can say something like that IMO.
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Thay also don’t terminate the charge either. I’m guessing any thing you teperaaly plug in when charging the battry is the charger. Seems that’s the only constant.
The charge system needs to complement what’s inside the battry and what temporarily plugged in to charge to make a complete chafing system.
Ps in power tools it’s common to have the balance circuitry in the charger because it’s Easter to cool that way
soooo, anyone with a lipo pack or no sense of self-preservation want to try out this nonsense? There’s also a 3.3kW version if you’re feeling spicy
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When you need to install a new circuit in your house to charge your board
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