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sharkbite
14-12-2018, 11:00 AM
I have some time over xmas to tinker...

While my lx90 works just fine with a 12v Sealed lead acid battery,
the cabling offends my sensibilities so......

i have some 26650 Lipo batteries doing nothing that
just happen to fit in the stock battery housing on the mount.

The Lx90 has two battery compartments allowing for 4 C cells each,
nominally requiring a 6 Volt input...which will vary depending on battery condition..

2 Lipos each side will supply of them produce way too many volts and could potentially
damage the motors(?), so i'm planning to incoporate a 6v regulator on each of the 2
battery packs.

Does anybody know whether the mount expects a 'proper' 6+6=12v,
or if i should set it just a little bit higher?

I ask this, as even the old SLA sits at about 13 volts most of the time...
just not sure how voltage change affects performance on this mount...

iborg
14-12-2018, 02:02 PM
Hi Sharkbite


I also have an LX90 and very much like your idea. When I search "26650 Lipo batteries" most of what comes up refers to Li ion batteries. Such as in the link below.


Are you confident that you have LiPo batteries? If so, do you have a link?



https://www.jaycar.com.au/26650-rechargeable-li-ion-battery-3400mah-3-7v-nipple/p/SB2315


Philip

sharkbite
17-12-2018, 09:10 AM
Hi Philip - oops, you are correct, mostly Li ion at 3.7v (which is what i have, and why i need a regulator, as fully charged they can hit over 4v)

jaycar also sells the 3.2v Lipo 26650 - which may not need regulation?
(I dont know for sure, as i dont know the tolerance of the lx90 to over volt, nor what these things charge to.)

i think i'll start with an exact 12v and see how things go

iborg
17-12-2018, 02:37 PM
Hi


Sealed lead acid batteries, fully charged are up to 13.8V, half of that is 6.9V.


With the LiPo 26650 batteries at 3.7V x 2 = 7.4, just add a diode, big enough to handle the current.


This one should be fine

https://www.jaycar.com.au/6a10-6a-1000v-diode/p/ZR1024


I think it drops 1V and can handle 6A.

On each side setup 2 batteries plus one diode ((2 x 3.7V) - 1) x 2 = 12.8V


No problem! I think!!


If you go with the LiFe batteries, don't even need the diode! but, it would provide protection to batteies inserted backwards.



LiPo 3.7V

https://www.jaycar.com.au/26650-rechargeable-li-ion-battery-3400mah-3-7v-nipple/p/SB2315


LiFe 3.2V
https://www.jaycar.com.au/26650-lifepo4-battery-3000mah-3-2v/p/SB2317


I hope his makes sense.


At these prices for the batteries, I will for leads to die before thinking of doing it.


Have fun


Philip

AussieSky
18-12-2018, 09:11 PM
Pretty sure the voltage drop across the diode will be about .6V, but that would still keep you in the safe range, ie: about 13.6V

sharkbite
19-12-2018, 08:21 AM
Thanks Guys...

making the 'leccy bits are no problem for me

My question was more around what the mount expects or can stand...

I dont know if it is designed for a wide range of voltages, as one
would expect if it was supposed to work off a battery.

A regulated supply is a bit different....if i set it too high it might blow
the circuits, if i set it too low the controller could register an undervolt situation, and either slow down, or annoy me all night with stupid alarms.

I'll try dead on 12v and report back here with any findings.

cheers, and thanks for your responses.

iborg
19-12-2018, 07:00 PM
Hi



I misread the data sheet, maximum forward voltage (at 6A) is 1 amp.


I just measured one as 0.55V.


For a constant voltage supply, I would still set it 13V, just to be lucky!


Philip