A YZ Power 2A 42V charger with a 5.5x2.1 plug
plus one of these
and these
and you’ll need a BMS as well
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IM in Aus, and the fuse links weren’t working, is this the? 5pcs 7.5A 7.5Amp Regular Standard Blade ATO Fuses for Cars Trucks Auto Brown | eBay
No, those aren’t rated for a high enough voltage.
Mouser broke their links … again…, I fixed them and added the manufacturer part numbers for ease of NON-mouser searching as well.
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Did we ever work out what the best charger was?
Will never happen IMO.
Some feel lowest cost is most important. Others only want certain features or they won’t buy it.
Think of what would happen if you asked what the best vehicle was. It depends on what you’re doing with the vehicle…Dakar Challenge? Just picking up the kids from school? This makes a huge difference towards what would be considered the “best” choice.
Same thing for a board or charger or just about anything else. We all definitely just want one single best option to choose so we don’t have to hunt around, compare specs, read reviews, etc., but there are so few things that let us get off that easy…chargers definitely included. 
If you’re looking to buy a charger post what specs/features you need, or don’t want, and I’m sure you’ll get some great recommendations though.
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End of discussion 
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excuse my lack of knowledge here:
Why? I just buy chargers from WATE that have the auto shutoff and i’m good to go. Price is very reasonable too.
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Why what? Sorry, I don’t understand what you’re asking about.
Why isn’t there one charger that’s perfect for everyone?
Some want adjustability, some don’t want to deal with that complexity.
Some want high amperage, others don’t want to pay for that.
Some want a display with lots of data, others just want a red/green LED.
Etc….etc…etc…
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OOOh okay. In my mind, adjustability and displays were fancy extra features that don’t change the quality of the charge itself. I was solely thinking of “what can charge my battery safely” and nothing else. Seems to me that 99.99% of people just want a charger with a decent amperage and auto shutoff. Nothing more.
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What’s the best way to confirm that a charger is actually turning off when the pack is full? Amp meter on one of the charging cables?
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That would work. But the current levels before shutting off can be very low. Hmm…I guess that wouldn’t matter though as shutoff = zero amps.
Another method is a multimeter on DC volt min/max. If the voltage has dropped from the max then current flow has probably stopped and the pack is settling down to its true resting voltage.
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I dont understand why the charger has to be the one that auto shuts off. The BMS should be doing this, no?
For a full charge, no. I was wrong, some BMS’ can detect the charge current and determine when to shut off for a full charge. There are advantages and disadvantages to both approaches (charger or BMS shutoff).
Charging isn’t done when the cells each reach 4.20V (ideally). The charge needs to continue until that voltage is reached and the charge current has also dropped to, typically, 1/10th of the bulk charge rate. This is the “topping off” of the cells.
If the BMS shut off charging when the pack reached 4.20V/cell the pack would be undercharged. This can be used to extend cell life a little bit but it’s the charger that normally needs to determine when the pack is fully charged (unless a very smart BMS is used).
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I was under the impression that balance bms do this exactly… am I mistaken?
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The balancing, or lack thereof, won’t have any effect on whether a BMS can detect the charge current flow but if the BMS is designed to do that (some can, some can’t) then it could be used to terminate the charge at the correct time.
Thanks for reminding me this can be done via a BMS. My previous post is incorrect and I will update it.
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so if we use a good BMS that does this, then the auto shutoff feature is just redundancy, no?
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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