Yet another "Is this battery okay to use" question

[graylensman]

After reading a metric buttload of threads about batteries, I came away knowing much more than I did...and achieving no more clarity than before. So...

I have a 12v lithium battery used by a Ryobi hand drill. Is it okay to use in a launch controller? I'll be launching MMX mostly, and some LPR occasionally.

 

[kuririn]

If an Estes controller with a 6 or 9 v. power source can pop an Estes starter, don't see why this would be a problem. Just make sure it's fully charged and that the battery holds its' charge. Could go into a long treatise about volts and amperage, but you probably already read that. Since you're not going to use this to ignite a seven engine cluster, higher amperage, like in a car battery, is not a concern. Personally, I've used a 40v. li-ion lawn mower battery to ignite my Hydra 7 and Cluster Duck successfully. Both use a 7 engine cluster.

 

[SteveThatcher]

should work just fine, but... the battery pack may have a high temperature limit and shut itself off when it gets too hot and that could be just environmental. Trying to use it on the Salt Flats or desert area may be problematic. If you are in temperate areas, then you shouldn't have an issue for that. Try it and make sure you can ignite a worst case load just to make sure they didn't throw in a current limiting circuit. I am looking at it from a engineering perspective and how I would design something like that. Ryobi may or may not share my thoughts...

 

[graylensman]

Thanks for the succinct responses! I'll wire it up soon, and report back.

 

[FlyBy01]

should work just fine, but... the battery pack may have a high temperature limit and shut itself off when it gets too hot and that could be just environmental. Trying to use it on the Salt Flats or desert area may be problematic. If you are in temperate areas, then you shouldn't have an issue for that. Try it and make sure you can ignite a worst case load just to make sure they didn't throw in a current limiting circuit. I am looking at it from a engineering perspective and how I would design something like that. Ryobi may or may not share my thoughts...

I live in Phoenix, AZ. What type of battery would you recommend for it's too darn hot climates?

 

[SteveThatcher]

I live in Phoenix, AZ. What type of battery would you recommend for it's too darn hot climates?

that is a good question. My answer you quoted was about a power pack designed for an electric drill. I actually would suggest looking into the LiPo car starters. They are obviously high current and the battery jump connector are typically not protected for max current (probably depends on the manufacturer). They are supposedly designed to jump start a car in an emergency. It seems to me that they shouldn't care about environment temperatures as long as the temp doesn't exceed whatever the safe limits are for the batteries (that should be in the users manual). Keep in mind, I am only conjecturing that the Ryobi battery pack would have protection circuitry in it. If you look at the car starters, you will need a cable that attaches to the jumper connector. The 12 volt cigarette lighter connector will more than likely have protective circuitry on it. A friend of mine who builds launch GSE found that to be that to be the case with one he purchased at HarborFreight. It also had a proprietary jump connector so I printed a connector housing for it and turned down some brass rods for the contacts... solutions are always just a few steps away...

As for doing a launch in Phoenix, I would think that a cooler could even be used to keep the battery pack from getting too hot if there are environment limits. Personally, I have a Duracell car starter (sealed lead acid) that I use at launches and have never had an issue (it just weighs a lot...).

 

[Rex R]

LiPo's AFAIK do have a temperature upper limit of approximately 140ish F* so, you would want to keep them in the shade and off the ground(if possible) preferably with a breeze(not in a sealed box). 105 - 110F is/was** a safe working temp.
*before you run the risk of a thermal runaway
**at least it was a few years back.
Rex

 

[SteveThatcher]

LiPo's AFAIK do have a temperature upper limit of approximately 140ish F* so, you would want to keep them in the shade and off the ground(if possible) preferably with a breeze(not in a sealed box). 105 - 110F is/was** a safe working temp.
*before you run the risk of a thermal runaway
**at least it was a few years back.
Rex

I did a quick look see and it looks like the 105-110 F is still accurate for working temp. Definitely in the shade and off the ground. Made me think of a battery operated cooler where the battery pack is keeping itself cold... along with drinking water...

 

[Rex R]

a computer case cooling fan(3") would likely suffice, just need to keep the temp down to air temp,(you probably will not be wanting to fly rockets when the temp is over 110f).
Rex

 

[SteveThatcher]

been to Blackrock several times and the salt flats last year... I never seem to launch rockets in the cooler temperatures...