Noob charging question

[Vito413]

This is probably obvious to everyone except me.
When I charge a lipo there is a readout of mah. My question is, Is this a measure of the mah that was put back into the pack or is this telling me that this is what is left in the pack. If it has 485 or something else, is that what the charger put into the pack to make it to capacity, or is that the amount of mah that is currently in the pack.
I have killed expensive packs by storing them full for a long time, and I want to make sure that the packs will hold the full amount of mah and not have full voltage but no mah to really do anything.
Thanks and wish me luck on my charging.

Vito

 

[ElectriSean]

On the chargers I've seen, this is displaying the amount of charge put back while charging. Most decent chargers will have a storage mode, which will charge to around 3.8v/cell which you should use if you're not going to discharge within a day or so.

 

[kdobson83]

I would pay less attention to the MAH and more to the voltage if your trying to decipher what's charged/storage/dead.
Fully charged a lipo will read 4.20 volts per cell. If you charge/dishcarged it to storage, each cell should read 3.8 volts per cell, roughly, because I think mine does 3.83 or something silly. But as close to 3.8 as you can should suffice. And the obvious would be a used battery, will have less than. 3.8 per cell. I have my low voltage cutouts and alarms set to 3.4 volts per cell but this number is still up for debate. Some people don't drop below 3.6 volts. I have found in most flights at 3.5-3.4 volts when charging it will do put back about 85% capacity.

Anyway, the mAh you speak of would be what the charger put back into the pack when you charged. Kinda like putting gas in a car. Your gas gauge will tell you how full your tank is, aka voltage, and when you fill it up, the pump will tell you how many gallons it put in, aka mAh. But your gauge doesn't show how many gallons you have left. I'm totally making this more complicated than it is. Lol Anyway, hope that helps clear things up a tad.

 

[Vito413]

Thank you both. I was pretty sure that it worked that way. But I had no way of supporting this. We all know how informative the user manuals are, and the web pages are in German.
So now I will go and set a discharge/storage mode for my packs.

I also have another question. When I charge the packs, in order to charge faster I can set up a charge amperage of roughly 1 amp for every thousand mah? For instance if I had a 3200 pack I could charge it at 3.2 amps? Is this a correct way of thinking?
Is there a faster way to charge my packs?

Thanks again.
Vito

 

[Fyathyrio]

You are correct, set charge rate equal to the battery capacity. You can charge most lipo batteries at a higher rate, perhaps 2 times, even as high as 5 times the capacity, but this will shorten the life and also lead to slightly undercharged batteries.

One good way to charge faster is to parallel charge, where many batteries are charged at once. It's a simple and safe process once you understand the details. Batts must be same cell count (2S, 4S, ect), and must be at nearly the same voltage (+/- tenth volt per cell is fine). They do not have to be the same capacity, you can charge a 1000mah with a 3500mah, for example. Then, add up the capacity of all cells and charge at that total rate. This is done using a parallel charging board, they can be found for about $15 on eBay, ect with a variety of battery connectors. I recommend avoiding the octopus looking ones made out of bundles of wires soldered together, the joints are usually weak and can fail.

 

[kdobson83]

Here is the exact parallel charging board I use

XT60 Parallel Balanced Charging Plate Charging Board for imax B6 B6AC UN-A6 charger,Rechargeable Lipo Lithium Battery Adapter Expansion Board by Weyland https://www.amazon.com/dp/B06XW6XCZ3/ref=cm_sw_r_cp_apa_IQOXAbM0BVCG9

Just read up on how to use them. There is LOTS of info on parallel charging out there. My main points I'll add real quick, charge same cell counts only, so only 3s or only 4s at the same time. And the second, batteries must be close to the same voltage. Now, some people say that it must be super close, like .03 volts difference, but other say as long as it's with in .1 they've never had issues. Basically, don't charge a dead battery and a storaged battery at the same time.