Lipo noob shopping list.

[wineboyrider]

Once my lipo arrived, I realized charging outside in 100+ temps might be a bad idea, at least in a metal box that might be 150F.

So looking aroung the house, I realized the fireplace is a pretty good place for fires. So I'm just using the hearth, and putting the spark screen in front of it. anything really bad happens, I can always poke it into the firebox. I heat the house solar now, and rarely use the fireplace even in winter. As soon as I start charging, I look at the voltage at cell level, and can stop if one is really low. So nothing bad should be happening.

I still need to get a battery medic so I can check before charging. If my charges allow that, I haven't yet learned how, but it is easy to check em at the start of the charging.

I'm liking the chargers. Not sure if they are the best, but they sure are smarter than the ping chargers I've had. I like it that they can charge pretty much anything you have. I haven't tried to adjust the top of charge down some, if it can be. Sounds like a good idea to undercharge a bit, even though I most likely will be losing them to old age, or track abuse rather than cycles.

For a power supply, it's working ok to use an old half dead sla to run both chargers at the same time, while it is hooked up to a dumb 12v 6 amp battery charger I've had for about 20 years. Hooking it straight to the 12v dumb charger didn't work, not good enough current. But once attached to the sla to smooth it out, it works fine.

I got 6 of those 5s lipo cells you recommended as well as some buzzers. I also got some new Ping BMS's on the way and was hoping the new HK charger will help me balance my lifepo4 as well. When I get the lipo I will be able to configure a 13.2ah 38v pack or a larger voltage pack for that short burst to work

 

[dogman dan]

Glad I could help. I posted my entry into lipo just to make some basic info easy to find for the lipo virgin. I really like the chargers. I kinda wish I had the plugs to charge my ping with it. Tempting to add some extra balance leads to use the balancing function of my lipo charger 6s at a time.

I'm lousy with a soldering iron, so I had trouble putting the plugs on the buzzers. Hopefully you are better at it. I ended up adding an extra wire to the main leads to connect the buzzer and locate it on the handlebars.

I considered keeping track of Amp hours used critical to using the lipo with no bms lv cutoff. The idea is to keep depth of discharge where you never even see the buzzer beep once, let alone go off at 3v. Have you got any kind of wattmeter?

 

[wineboyrider]

Watt meter? I've got a turnigy watt meter and it's mounted where I can look down at my controller and see how much juice I've used. So is the actual voltage of the pack the best measure to know when to stop or the Ah reading??? or both?

 

[dogman dan]

Ah used would work once you know what number to look for that leaves you plenty of reserve. Bottom line is never let a cell get below 3v From what I've read, the drop from 3.5v to 3.0v can happen really fast so keeping a fairly large % in reserve could be a good idea for day to day use. So say you have 10 ah, stopping by 8 ah would be good practice, if nothing else for good cycle lifespan.

But sooner or later you will end up cutting it fine, and would be watching the voltage. The beeper should save you, but better to never hear it go off ever. I have seen the lv beepers called, notification that you just killed your battery. But if you do hear the first single beep, you want to stop right away. I think that first beep happens around 3.3v For my 15s lipo, I'd be looking to keep the voltage above 50v.

 

[dogman dan]

Continuing the lipo noob experience, here is how I'm charging them now that I'm starting to use em. A few old sla's from the first ebike plus 12v chargers are the power supply. The sla's just smooth out the rough current from the dumb 6 amp charger. The lipo chargers won't run on current straight from the charger, but hooked up to a nearly dead battery, then they work fine.View attachment Ghetto charging station..jpg Where better to charge than the fireplace?

Trying not to have a fire while riding, I've made political signs into tight fitting lipo cases. 2 stick, 3 stick, and 4 stick. These then go into the usual metal toolbox. I've taped the low voltage buzzers to the end of the packs for now. View attachment Coroplast lipo boxes.jpg

 

[dequinox]

The lipo chargers won't run on current straight from the charger, but hooked up to a nearly dead battery, then they work fine.

A lot of those car battery chargers are straight-up constant current...meaning they push 6amps no matter what (forgive me if I'm being completely redundant and you already know all this... ). With that the voltage varies...so the chargers are probably not getting the voltage they need to run. The dead-ish battery is actually not a bad idea, seems to me it would act sort of like a capacitor. Anyways you might want to get a CV (constant voltage) lab supply or something similar. Those old CC car battery chargers aren't the best thing for this from what I can tell...

 

[dequinox]

I've spend a lot of time window shopping on HK and I've recently noticed something. If you sit and stare at a product long enough, that is just leave your browser on one thing, the website will offer you a deal on that product. The $105 new nano turnigy packs were offered to me for around $97 a piece. They only offer it to you once though...and that I think is if you are a signed-up member. Food for thought the next time you bulk-order lipo.

 

[dogman dan]

I'm considering just getting a big deep cycle battery, or even just a new battery for my car. My wimpy little 50 watt B6 chargers don't pull that hard. When I go racing, I may be able to just pull the charging I'll need out of the battery with no need for a plug out in the pits. But for now, this is actually working pretty good. Two chargers running at once will run without overcooking the little sla.

And for now, I don't have to buy more stuff for lipo, unless it's more lipo. I need to make a set of connectors though, so I can paralell up the three old sla's.

Got my other computer watching some 4s lipo on HK right now. 8) Holding my breath waiting for 5s 5ah 30c to restock isn't working so good.