Seeking Round 4 or 8x 21700 Battery Carrier

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Laser Project
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Seeking Round 4 or 8x 21700 Battery Carrier

Hello, I just joined, Matt Smith wrote me suggesting I ask this question in this forum.

I'm looking for a round 4 or 8 battery carrier for 21700 protected or unprotected cells. I can use series-parallel or even just series or parallel strings in the holder for my high current project which can use one summed output, or several individual ones, i.e. 4.

I don't care what the carrier costs, within reason. Can someone point me to one? High quality preferred. The carrier shown in this YT video reviewing a huge BLF flashlight is perfect, it can be viewed at minute 2:58. My understanding is that carrier will be able to use 18650 or 21700 cells.

Budgetlightforum Giga Thrower 4 25,000 Lumen Flashlight: https://youtu.be/tM9XL4rRw2A 

 

Edited by: Laser Project on 04/12/2022 - 12:46
Lixivium
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I doubt the GT4 battery carrier could fit 21700’s. Does the gt94x have a 8*21700 carrier available?

raccoon city
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It's a pleasure to know you, Laser Project!

217_milla

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Thank you for the welcome.

 

The carrier shown in that video was stated to be a new upgrade, but from what I've been able to find, it is not being offered, not yet anyway. I saw something about it somewhere which caused me to believe there was a 21700 version of it being planned. Sure would love to have either one, 18650 or 21700.

Lixivium
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Laser Project
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Great, thank you so much, don't know why I couldn't find that on my own. Ordered! I found they offered both sizes, for the 18650 and the 21700, bought both. I am so happy Smile

 

18650 8X battery holder is for the GT94 GT4

21700 8X battery holder is for the GT94X 4XSBT90.2 - I decided to buy the flashlight too Shocked

Laser Project
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Update on the GT94X, received it along with some extra battery holders but the four 21700 batteries are all in series in each holder producing over 16 volts DC for a fully charged set of Li-ion batteries. I cannot have over 12.6 VDC or so voltage for my laser diode drivers I want to use with this flashlight as a host Sad

Good news is there is a fix for this, I can put a solid aluminum dummy battery in one of the four cell slots to reduce the voltage to about 12.6 VDC. The bad news is I thought I was getting a holder which had two batteries in parallel and series with the other two to double the capacity at 8.4 VDC which is not what I got. Appears the fix for people putting unequally charged cells in a single holder was to make everything in series and use a driver and LED's which could take the extra voltage. This doesn't fix the issue of someone putting in a second pack which is not equally charged, unless they have a series diode to prevent back charge from the front pack.

I would be better off with a 18650 series-parallel pack except the 18650's don't give me the high continuous current the 21700 batteries can.

 

 

The_Driver
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Laser Project wrote:

Update on the GT94X, received it along with some extra battery holders but the four 21700 batteries are all in series in each holder producing over 16 volts DC for a fully charged set of Li-ion batteries. I cannot have over 12.6 VDC or so voltage for my laser diode drivers I want to use with this flashlight as a host Sad

Good news is there is a fix for this, I can put a solid aluminum dummy battery in one of the four cell slots to reduce the voltage to about 12.6 VDC. The bad news is I thought I was getting a holder which had two batteries in parallel and series with the other two to double the capacity at 8.4 VDC which is not what I got. Appears the fix for people putting unequally charged cells in a single holder was to make everything in series and use a driver and LED's which could take the extra voltage. This doesn't fix the issue of someone putting in a second pack which is not equally charged, unless they have a series diode to prevent back charge from the front pack.

I would be better off with a 18650 series-parallel pack except the 18650's don't give me the high continuous current the 21700 batteries can.

 

You can try modding the carrier by cutting the traces on the PCBs and soldering small wires to get 2S4P.

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Thank you for the suggestion, I may end up needing to do so.