Model Boat Mayhem

Technical, Techniques, Hints, and Tips => Batteries & Chargers => Topic started by: me3 on July 10, 2014, 10:49:30 am

Title: Making my own battery pack
Post by: me3 on July 10, 2014, 10:49:30 am

Hi all, again  :-)

I need a small battery pack to run my small model from. The batteries it came with are only 1750mAh. I would like to have a few more to get better run times. Could I connect 6 NiMH AA Batteries together? This would give me 7.2V (or thereabouts) and say I got the most 'basic' at 600mAh each that would give me 3600mAh. Am I being mad or could this work? Would they still charge normally off a model charger or cant you do that?
Thanks,
Reece

Title: Re: Making my own battery pack
Post by: Calimero on July 10, 2014, 10:55:29 am

Yes it would work.

You could also get a 2S LiPo but that would require a LiPo-aware charger (40$).

Title: Re: Making my own battery pack
Post by: Netleyned on July 10, 2014, 11:01:06 am

6x600 in series will give you 7.2V @ 600mA not 3600mA


Ned

Title: Re: Making my own battery pack
Post by: Calimero on July 10, 2014, 11:07:32 am

Indeed.


600mah AA size is pretty weak though. They hover around 2500mah these days. Note quite 3600mah though.

Title: Re: Making my own battery pack
Post by: inertia on July 10, 2014, 11:08:42 am

Joining NiMH batteries into a pack isn't an easy job to do properly without a spot-welding machine. Not enough heat and the solder won't melt, but too much and you will fatally damage the cell. Why not buy a pack ready-made? These folk do hundreds of different types - I've picked out one which would suit you http://www.componentshop.co.uk/7-2v-aa-2600mah-flat-6x1-battery.html (http://www.componentshop.co.uk/7-2v-aa-2600mah-flat-6x1-battery.html)  There are others - have a browse.
DM

Title: Re: Making my own battery pack
Post by: me3 on July 10, 2014, 11:12:03 am

Okay then thanks, Forgot about how amperage works! haha, only a few weeks ago I took the As-Physics exam  :embarrassed: . That makes it a lot easier Inertia, I was hoping there would be a company that makes lots of sizes

Thank you,
Reece

Title: Re: Making my own battery pack
Post by: dreadnought72 on July 10, 2014, 11:51:32 am

To avoid soldering rechargeable AAs, you could pick up one of these (http://www.maplin.co.uk/p/6-aa-battery-box-hq01b). (6 AA battery holder). £1.59 from Maplins.

Andy

Title: Re: Making my own battery pack
Post by: Netleyned on July 10, 2014, 01:45:37 pm

Quote from: dreadnought72 on July 10, 2014, 11:51:32 am

To avoid soldering rechargeable AAs, you could pick up one of these (http://www.maplin.co.uk/p/6-aa-battery-box-hq01b). (6 AA battery holder). £1.59 from Maplins.

Andy

These are no no for waterborne activities as they
quickly corrode and cause intermittent power transfer.

Ned

Title: Re: Making my own battery pack
Post by: grendel on July 11, 2014, 01:05:41 pm

also if you get a short, the springs melt into the plastic and disconnect.
Grendel

Title: Re: Making my own battery pack
Post by: dreadnought72 on July 11, 2014, 01:56:41 pm

Isn't that a safety feature?  %)

Andy

Title: Re: Making my own battery pack
Post by: inertia on July 11, 2014, 02:05:57 pm

Quote from: dreadnought72 on July 11, 2014, 01:56:41 pm

Isn't that a safety feature?  %)

Andy

Andy
I hope that the smiley face indicates tongue-in-cheek. There are some folk daft enough to think that's a good idea.
DM

Title: Re: Making my own battery pack
Post by: Netleyned on July 11, 2014, 05:27:42 pm

And fuses are a lot cheaper than a meltdown :}

Ned