How to test amp hour

[Lil Giants]

Thanx for the reply Nathan. I should note that the Venom lipos started out working normally w/4600+ & starting on the charger above 12.5v. I think it was sometime after seeding when capacity started to drop, the packs would have been left fully charged for a month or longer. I can't remember when exactly they started to puff outward, but they have ballooned quite a lot now.

I was getting about 50mins run time with casual digging with the bucket, and around 40-45mins ripping - maxing the hyd press constantly.. about 10amp draw?

Cheaper pack? they run me about $65ea, what do the better ones cost? I have a 3300NiMH 7.2v paxk that's been in my bd trl 6 - 7yrs now, pretty good life span for a pack, though it's not a huge drain running the pump for less than 20s per load.

The original 3 lipos might be around 250 charges, I always let packs cool before charging, does that matter either way?

One of the three, I forgot the hoe on over night & drained the lipo well below, I tried the trick with the NiMH setting to get the volts back up & it worked with no issues for many recharges later. I charge my lipos in a large glass cookie jar with its metal lid, it all sits in front of me while I watch tv & surf the net.

Originally Posted by FlyingBeagle

If they are going to be sitting for a while I store them at 3.6V~3.8V per cell. I never store them for more than a week fully charged.

What's the reason for that?

A lipo that is more than a little puffed is dangerous. You should think about getting rid of it. It is not worth burning down your house or damaging a plane or the piece of equipment it is powering. Youtube has plenty of videos of LIPO fires and counting mine I have seen three in person and they are pretty wild.

Yes, I do see your point.. and my original 3 have ballooned out quite a bit!

Today I set my packs out in the yard & shot one of them with my .22 rifle about 5x to see what would happen.. maybe it would worth filming..


nothing happened!

I walked over to it carefully after 5mins of distant observation to only smell a sweet aroma coming from the pack & a faint hiss. So back to my rest & emptied my clip into the other two with no drama to be seen. Went into the house to put my gun away (took a couple mins) and came back out to clean up the mess with a shovel when all of the sudden the fireworks started with one of the last two shot! Sparks flying pretty good & then it burst into flames!!! Then other one was like a smoke bomb, big cloud of white smoke, that's all. Scraped them all up & dumped the remains in the burning barrel.

All 3 were fully charged prior to shooting at them, but they sat 4hrs on my cement step in -10C before I destroyed them.

You may want to up your voltage cut off a little to help lengthen your pack life and always balance charge them.

There's a noticable drop in pump speed a few mins before the cut-off kicks in, I'll change packs then & see what the voltage says. Might be a good thing to prolong lipo life. Thanx for the info FB.