Battery Charging

[Gussler]

This is not really a problem - Just a question.

So today I finally ran out of one of my AK47 batteries (8.4V 3600) and I was wondering: are dischargers absolutely necessary? Before I go out and buy one I wanted to ask if it really matters if I just blank-shoot until the gun does not fire anymore and then charge up the battery? If it does matters, what can happen to the battery? Worth a purchase or not really?

Thanks.

[Renegade)]

Im gonna answer one part of that, dry firing your gun=gun murder, never do it unless very minimal. Dischargers are worth it, Nimh doesnt always have to be, but helps, as well as a good chargers, its NiCd u really wanna discharge to prevent memory charge.

[LUTNIT]

Straight dischargers like the TM/G&P/etc. dischargers that are just resistors are hell on your batteries, you can easily kill your packs with one of these chargers. I recently had dealings with someone on ASC who used a "grenade" discharger (don't know what brand it is) and all this persons batteries where toast.

NiMh batteries should be discharged once in a while, usually once or twice a year depending on how often you play. NiCd batteries shouldn't be discharged before charging every time, this can damage them. Discharging NiCd packs every 4-5 charges is good enough.

If you discharge your packs you should NEVER discharge past 0.9V/cell (optimum capacity is 1.2V/cell.) Discharging past this point is very damaging to your batteries. You want a good charger/discharger that has a computer controlled discharge sequence that monitors voltage.

Also NEVER store your batteries empty. Long term storage with 40-60% charge in the fridge is best, I usually store my batteries between games fully charged simply on a shelf.

[Dark-Angel]

in the fridge or freezer? i heared rechargable batteries lose more of there power when in a cold evenromint unless its a nonrechargable because of the chemastrie in them, not sure if this is true.

[Mantelope]

Originally Posted by Dark-Angel

in the fridge or freezer? i heared rechargable batteries lose more of there power when in a cold evenromint unless its a nonrechargable because of the chemastrie in them, not sure if this is true.

They get "used up" faster if you're draining them in a cold environment. Storage in a cold environment is an entirely different matter.

[Styrak]

Originally Posted by Mantelope

They get "used up" faster if you're draining them in a cold environment. Storage in a cold environment is an entirely different matter.

This is true. It's pure science. Chemical reactions (power being used up in the batteries) happens slower the colder the environment they're in.

[CDN_Stalker]

I read a few times that discharging NiMH batteries can destroy them, sometimes causing them to catch on fire. Clarification is required, maybe make this a noob sticky as well.

[Gussler]

I appreciate all the comments and help, but now I still don't know whether I should buy a discharger or not. So far I only have two NiMh batteries - both 8.4V - 3300 and a 3600 mAh.

I have never used the 3300. when I tried it last night it wasn't even charged so I just charged it up overnight. The next morning the battery felt pretty warm - normal I hope? (but it works now). I have used the 3600. It ran out last night. On most sites I've researched, I read that with NiMh, discharging is not that necessary. That's sort of the idea I got from most of the comments posted here... so I just charged up the 3600 this morning and it works now (but it wasn't warm. why was the other one warm).

Thanks

[ThunderCactus]

batteries heat up when charging or in use, fact of nature due to the reaction going on, the wires get REALLY hot lol
you dont need to discharge it at all if its a NiMh, discharging is for NiCd batteries. I got a 3000MaH batt thats 4 years old, still holds 3000MaH

[LUTNIT]

Overnight charge?

You should charge NiMh batteries at around 1C so for your 3300mAh pack thats 3.3A (3.6A for your 3600mAh pack, etc.) and it takes less than an hour. Charging a battery too slow can cause problems including a memory effect (same thing that happens to NiCd packs when you don't discharge them before charging too often.)

[CDN_Stalker]

I've been using the same 8.4V 3300mAh battery for about three years now, that's about 15,000 rounds worth of testing and gaming, maybe abour 40-50 game days, and it's still going strong and I only need to charge it every couple game days (I only shoot 200-500rds per game day), and I only ever charge it on 1A, ok, have done a couple quick charges at 2A or even 4A, but I make sure it's charged a few days before I play with it. It still is going very strong, never have discharged it except from use.

So, if you buy a NiMH, don't waste money on a discharger, it is a waste and could actually damage your battery.

[mcguyver]

If a NiMH battery gets hot enough that you can't comfortably hold it for 1 minute, then it's too hot and damage will occur if you persist in charging it that way.

An "overnight" cheapy wall charger is only good for ballasting your garbage bag at the curb. They do not detect peak charge, nor are they adjustable. They charge with constant current (usually) and care not if the battery gets overcharged or damaged.

As a general rule, your charger should cost equal to or more than your battery. If you buy an $80, you should not be using a $20 charger.

Excessive heating and overcharging of NiMH batteries can lead to gas production at the anode and cause electrolyte to escape, eventually killing the cell. 1 dead cell in a pack of 7 (8.4v) is enough to render the pack useless.

No battery should become hot when charging. Slightly warm, maybe, under extreme fast charge may be permitted once or twice, but not on a regular basis. And Lutnit was right. Charge your batteries at 1C (1 x mah-rating) or less and discharging is not required for NiMH, but it won't hurt them to do it once in a while.