Lipos Will Burn on Charger

[Jimbobjr]

I like the idea of using a BBQ grill for a charging station. Should contain a fire. Rather loose a charger, etc than the house. Not sure what temperatures they burn at but that should help. There is a video on Youtube of someone unwrapping a lipo and putting the metal wrap into a container of water and it goes up in smoke and then created a small explosion.

Grill is a good idea for guys living in townhouse or don’t have a garage. What ever you charge in you need to keep it out of a living space. Even if you contain the flames and mess the surrounding area will stink forever...

 

[tntpoof]

A Ozone machine will take the stink outa anything

 

[Mtbmatty]

So what causes the internal resistance to rise. Is it how the battery is charged/ used, or just luck of the draw??

 

[Jerold]

So what causes the internal resistance to rise. Is it how the battery is charged/ used, or just luck of the draw??

My (limited) understanding is that age, charge/discharge cycles, abuse (over/under voltage, not using storing properly, shorting) or damaging the pack can all lead to higher IRs. It's a chemical thing so there are probably many other things that can cause it too.

However, you IR not a single number and it will change slightly depending (temporary) on the existing conditions of the battery and the environment. Meaning if you just pulled it out of your car or it's been sitting for 20 mins. Or maybe it's freezing vs a heatwave. This is because IR is not an actual resistor, the IR is the perceived resistance from the battery as a system. Most of that system is a chemical reaction.

If you are tracking your IR, because of the temporary effects, you will need to be consistent, record all the associated data and look at the trends. Consistency is accuracy and you have to look collect it in a controlled environment. Meaning under the same conditions each time. For example, maybe you run you car, do a storage charge, let it sit at room temp 70F (21C) for 3 hours, then check the IR. Get a routine.

The simplest thing to do is to read the documentation that came with the battery and follow what the manufacturer recommendations.

 

[FJC_GUY]

My (limited) understanding is that age, charge/discharge cycles, abuse (over/under voltage, not using storing properly, shorting) or damaging the pack can all lead to higher IRs. It's a chemical thing so there are probably many other things that can cause it too.

However, you IR not a single number and it will change slightly depending (temporary) on the existing conditions of the battery and the environment. Meaning if you just pulled it out of your car or it's been sitting for 20 mins. Or maybe it's freezing vs a heatwave. This is because IR is not an actual resistor, the IR is the perceived resistance from the battery as a system. Most of that system is a chemical reaction.

If you are tracking your IR, because of the temporary effects, you will need to be consistent, record all the associated data and look at the trends. Consistency is accuracy and you have to look collect it in a controlled environment. Meaning under the same conditions each time. For example, maybe you run you car, do a storage charge, let it sit at room temp 70F (21C) for 3 hours, then check the IR. Get a routine.

The simplest thing to do is to read the documentation that came with the battery and follow what the manufacturer recommendations.

I check mine at the beginning and end of each charge. They will usually be higher at the start and drop as it charges.

I have a couple of packs that were not dropped to storage for almost a week and those two show almost double what the rest of my packs do for IR. They are still at a decent spec but definitely higher and tend to have lower run times and in my Vorteks prone to tripping the LVC early from voltage sag, they are now crawler only packs.

There was a guy in one of the Facebook groups I'm on telling people that storage charging ruins batteries so you should just leave them wherever they are when you are done running until you charge them again. The worst part is some people were listening to him.

 

[Greywolf74]

So what causes the internal resistance to rise. Is it how the battery is charged/ used, or just luck of the draw??

My (limited) understanding is that age, charge/discharge cycles, abuse (over/under voltage, not using storing properly, shorting) or damaging the pack can all lead to higher IRs. It's a chemical thing so there are probably many other things that can cause it too.

This