Custom battery pack suggestions

[Boomer Sailor Vet]

Hello,

I need to make a light weight and compact battery for a big HID spotlight. The spot light is a Havis Shields CD-RH-HID 35W Xenon HID spotlight. The light calls for 12 volts and 3 amps. I was thinking about putting solder tabs on a few rechargeable batteries, wiring it up with a protection circuit, wrapping it in some heat shrink plastic, and carry it in a small bag with a shoulder strap. I found a thread discussing this same light but the information was from 2004. I'm sure there are new batteries since the thread was made. Any suggestions on what batteries to use for optimal performance are welcomed.

Thanks!

 

[HKJ]

For light weight you need to look at LiIon cells, the prismatic (rectangular block) type is best for this.

 

[BVH]

This has more power than you need because of its' 28V/16 Amp load but it's along the lines you're talking about in your post. You could make a smaller and lighter one.

http://www.candlepowerforums.com/vb...-Supply-for-the-Locator&p=3650603#post3650603

 

[CKOD]

Depending on the ballast voltage input range, you could use 3S Li-Po, (max of 12.6v) 4S LiFePO4 (13.6v resting voltage, 14.4 charging) , or 4S LiPo (16.8V max). Balance charging and a protection PCB is a must for the LiPo batteries, and is good but not required for the LiFe cells. If youre interested in stuff thats premade, K2 energy sells premade 12v LiFe batteries.
http://store.peakbattery.com/128vbatteries.html (look around online, not the only place that sells them!) and batteryspace.com has Li-Po/Li-Ion packs put together with and without PCBs (in addition to bare cells and bare PCBs for sale too).

Also, the LiFe batteries voltage match up fairly well with 12v lead acid, you could charge in an automobile if its electrical system was between 13.6 and 14.4V and just put a resistor in series to limit current for a quick and dirty charger. And some 12 lead acid smart chargers may be suitable for LiFe packs too, mind the current, and if there is a selection for Gel, AGM, and flooded lead acid, you should be able to use the gel setting if it charges the battery upto 14.4 volts or so. The el-cheapo transformer + rectifier ones that rely on the loading curve transformer and leakage current of the battery to find a float voltage would be bad, and ones that do desulfating would be bad too.

 

[Boomer Sailor Vet]

That's an awesome custom job.

 

[Boomer Sailor Vet]

Depending on the ballast voltage input range, you could use 3S Li-Po, (max of 12.6v) 4S LiFePO4 (13.6v resting voltage, 14.4 charging) , or 4S LiPo (16.8V max). Balance charging and a protection PCB is a must for the LiPo batteries, and is good but not required for the LiFe cells. If youre interested in stuff thats premade, K2 energy sells premade 12v LiFe batteries.
http://store.peakbattery.com/128vbatteries.html (look around online, not the only place that sells them!) and batteryspace.com has Li-Po/Li-Ion packs put together with and without PCBs (in addition to bare cells and bare PCBs for sale too).

Also, the LiFe batteries voltage match up fairly well with 12v lead acid, you could charge in an automobile if its electrical system was between 13.6 and 14.4V and just put a resistor in series to limit current for a quick and dirty charger. And some 12 lead acid smart chargers may be suitable for LiFe packs too, mind the current, and if there is a selection for Gel, AGM, and flooded lead acid, you should be able to use the gel setting if it charges the battery upto 14.4 volts or so. The el-cheapo transformer + rectifier ones that rely on the loading curve transformer and leakage current of the battery to find a float voltage would be bad, and ones that do desulfating would be bad too.

Thanks for the info. Very helpful. :bow: