Questions About 18650 Batteries

[Rader2146]

Dual battery mods are generally the ones that have resulted in venting, flaming, and explosion. Single battery mods are much safer. If you install two batteries in a mod and one is charged at a lower level than the other, the two will attempt to drain current from the higher charged battery to the lower charged battery, similar to two unevenly filled tanks of water connected by a hose. This happens are a high rate and Li-ion batteries don't like and can't withstand rapid charge rates. Heat is produced and failure usually occurs. Using a dual battery mod is playing with fire. One day you might install a charged battery with a dead battery by mistake. When you press the button, the two try to equalize and venting and hissing starts. I wouldn't do it. You are depending on the protection circuit to stop it once it starts. That might not happen.

It only works like you described in parallel setups, which are very rare outside of DIY Modder's builds.

In a series (aka "stacked") setup it is very common for one battery to drain faster than the other even if they start off at the exact same voltage. Effectively the exact opposite of what was described.

 

[RCMits]

The panasonics are the ones everyone raves about for the vamo

Why is it that the "eGO Vamo" sells with ICR batteries in the presentation package i wonder? I've used it a couple times and they seem to work OK. I am picking up the Panasonic CGR18650CH (this is corret right) for the Vamo.
@Rafier: RC racer here myself I think I'll just charge them with my Thunderpower charger

 

[WattWick]

Get 2 18350's. I get 30% better battery life out of 2 18350 800mAh's as opposed to 1 18650 2250mAh battery on my VAMO.

I though stacking 18350s was regarded as the least safe option? Something something about inserting two depleted 18350s registering as a completely fine 18650 and getting severely undercharged.

I think I'll just charge them with my Thunderpower charger

One of the perks of flying helis... not having to deal with cheapo chargers that don't tell you what's going on. I don't get how people rave about a $20 charger vs the crappy $10 chargers. I wouldn't trust either to keep my batteries healthy.

 

[Rader2146]

2 depleted 18350's would have to be under 2.1v per cell to be recognized as a single cell. At that point there isn't much hope for resurrection and the mod will cut off as soon as you push the fire button. There isn't enough energy left in the battery to maintain the voltage under load and the circuitry will cut the power.

The user is the most dangerous part of "stacking" batteries. When used with a little common sense, it is no more dangerous than any other configuration.

 

[WattWick]

Ye agree that the math doesn't add up. Was just thinking about the zmax safety warning I see posted on various fora.

Edit: Nevermind me, read the long posts on previous page. 2 cells at different charge states is the main concern.