Sun Fun Kits V4 User manual

Sun Fun Kits V4 Assembly Manual
Revision 1.0

Before you Begin:
Thank you for purchasing your Sun Fun Kits V4 DIY heated battery kit, diy battery kits make
assembling your battery quick and easy and only require basic tools and hardware to assemble.
We recommend having a basic understanding of DC wiring in order to assemble your battery
pack and you will also need the following tools:
● Hex driver set: 3mm, 4mm, 5mm, and 8mm
● Insulated drives for securing bolts
● Thread locking compound (such as blue Loctite)
● Kapton or PET tape 1” to 2” in width
● Double Sided Sticky tape
● Velcro style loop
● DC Voltmeter
● Standard scissors
● 90% isopropyl alcohol.
● Adjustable DC Power Supply that is able to charge up battery cells (3.65 volts, 20 Amps)
if manually balancing or standard 13.6v to charge the battery.
● 300-400 grit sandpaper
Optional:
● Electrical Safe Silicone sealant (for those looking to make a water resistant battery)
● Hot glue gun (if you wish to secure wires using this method)
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Preparing your battery cells:
Sun Fun Kits DIY battery kits support various prismatic cells, in this manual we will be using the
EVE LF304 type, however the process is the same for other manufacturers such as CATL,
REPT, Ganfeng and more, the V3 Kit includes spacers and other items to ensure maximum
compatibility for cells in this class (270-320 AH)
Certified Automotive Grade Cells generally do not require balancing; however, you may choose
to balance your cells, we have a video explaining this process.
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This process is explained in this tutorial video:
https://www.youtube.com/watch?v=JGbZozzCYvM
NOTE: if you are using an RTB (ready to build kit) the active balancer will assist in top balancing
your cells, simply assemble your pack, charge the battery at 5-20 amps and within 1-2 hours
your cells should be even balanced. Again, certified cells that are included with your RTB kit will
balance very quickly and the active balancer is included simply to assist balancing during high
amperage charging (over 80 amps).
Assembling your battery cells:
Starting with version 4 we are now including different cell shims or spacers, this allows users to
have a nice tight fit while also adding a third layer of insulation between cells. Version 4 includes
1 set of 1.5mm and 1.0mm shims (3 pieces each). The shims should be placed between the
inner cells and most installs will use about 1-3 shims (depending on the install method). For Sun
Fun Kits certified cells (LF280K, REPT 280, and LF304) you should be able to use 3 x 1.0 mm
shims to complete the install and have a nice tight fit, however for maximum pack longevity and
vibration isolating 3x 1.5mm shims will work the best.
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If you find difficulty installing the 1.5mm shims you may go down to 1.0 MM shims, you can mix
and match the 1.0 and 1.5mm shims as needed to suit your install preference.
Note: Based on customer feedback, we are now recommending you use the 1.00 shims
for the install, the 1.5mm shims should be used only by experienced installers.
Sidewall Heating Setup (Basic setup):
Version 4.0 includes 2 options for cell heating, a sidewall heating option as well as an
in-between cell heating option. Both options will allow you to heat up your battery for low
temperature charging (below freezing), however the sidewall heating method is generally an
easier install method. Note: both options will require the use of Kapton / PET high
temperature tape.
Version 4’s basic heating element includes dual heating pads on the inside walls of your kit. This
provides good heating and will raise the inside temperature of your case evenly. This method is
quite easy to install and is the only method that should be used if you are using grade B cells or
swollen cells as it provides the most amount of spacing for the cells.
Begin by placing your cells in a series configuration with the left side of the battery having the
positive terminal on the lower left and the negative terminal on the lower right.
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*Image shown is from the V3.5 Kit, but the install process is the same on V4.
Test fit the cells to get an idea of the installation; you will now need to prepare the cells with
shims. For this you have 2 options:
1) Place the cells and then insert the shims as you install the cells
2) Recommended: Tape the shims with Kapton tape to the cells and insert them together
into the case.
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Note: You will want to have the textured side of the shim facing the cell you installed, with the
smooth side facing outward. This will ensure the shim stays in place while you install cells.
*Image shown is from the V3.5 Kit, but the install process is the same on V4.
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Note: you may find some resistance installing your cells, this is because the EPE foam exerts
pressure on the cells to keep them in place; this is why we recommend adding the left most and
right most cells first and then adding the remaining 2 inner cells in the end as shown in the
picture below:
PLEASE MAKE SURE TO PLACE CELLS CORRECTLY IN THE ORIENTATION ABOVE.
V4 kits support various cells and depending on your cell height you may or may not need cell
spacers. For the LF280K, REPT 280 and LF304 cells sold by Sun Fun Kits, you will use the
1.5mm spacer on top of the case molded in ledges to raise the height of the support so that it
matches the cell. If you are using EVE LF280N or other cells that are 200mm tall you will need
the 2.5mm cell booster to raise the height of your cells.
Note: Starting with version 4, we are including a “Cell Puller” which will allow you to pull out your
cell if you have oriented incorrectly. The V4 kit holds cells tightly in place and this can be
challenging if you need to correct the orientation of a cell.
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*Take note of the 1.5mm Shims, these are needed to ensure a level surface for the main cell plate.
The side-mounted silicon heating pads will provide additional resistance to cells when they are
being installed, however, there is still sufficient space to insert the cells. It is recommended that
you do not install fully charged cells as they will make the process more challenging.
Once your cells are in the correct position; it is now time to install your cell plate. With our v4 kits
we have made our cell bracket universal and it should fit virtually all cells in the 270-320 AH
class.
Version 4 changes the 4x m5 screws mounting method in favor of 7x m4. This method provides
us with superior holding power and also ensures that the plate can not be mounted incorrectly
as 1 side has 4 mounting points while the other has 3. NOTE: Ensure the negative and positive
signs on the plate match your cells.
The side notches on the plate provide the opening channel to route your heating pad wires.
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Setting up heating using heated cell-separators (advanced):
The cell separator option is the more advanced heating option available in version 4 kits, this
allows 2 cells to be heated by a single silicon rubber heating element; 2 elements in total are
able to heat all 4 cells. The direct contact nature of this option means that the cells will heat up
faster so there is a potential of having a bigger delta in temperature between the cells and the
rest of the case. However, this method will provide for superior cell heating.
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