BatteryBlocs Assembly Instructions

Congratulations on your purchase of BatteryBlocs.  Now you can build a modular, repairable, rebuildable battery using only common hand tools. Take your time and geek out!

Put Cells in Cases.

Identify the positive and negative terminals of your 18650 cells. The negative terminals are flat, the positive have a small raised disc. If unsure check with a volt meter.

Grab a black case. Check the metal parallel strip and be sure that there is one and only one magnet in each hole of the potato chip. Center the parallel strip in the plastic case. Fill the case with the 18650 cells, one for each magnet, the negative side of the battery going into the black cases. The magnets will snap the cells in place.  The cap should fit loosely and have some wiggle room at this stage.

Grab a red case. Check the magnets, one and only one for each cell. Center the parallel connector strip. Look for the alignment arrows, they need to face the same way on both the black and the red cases. Place the red case on the tops of the 18650 cells already in the black case. The neodymium magnets will aid in alignment and will hold the case together until the nylon compression bolts are installed.

Assemble the remaining BatteryBlocs.

Assemble Blocs into a Battery.

Place the assembled Blocs into the desired battery configuration using the red and black to identify the positive and negative terminals. For serial wiring, multiplying voltage, the pattern will be red, black, red, black, etc. For parallel wiring, multiplying amperage,  blacks and reds will be together not alternating.

For split packs extra care is needed.  Assemble with full attention to the cells positive and negative positions.  If there are any sparks, pull the Bloc apart.  Wait a minute after the top is placed on and feel the batteries.  If you feel them getting warm you have misassembled them.  Pull the case apart and fix your mistake.

To connect the series wiring place the metal piece with 4 holes across two BatteryBlocs lining up the holes.(Except the 4P which has just one hole) You can move the underlying parallel plate a little to align the series connectors. Insert nylon bolts. Each bolt has a washer on each side.  When assembling split packs be sure NOT to bridge the gap on the chip with a washer.  If you do you will see sparks and you will have shorted the battery.  

To be efficient, you could also attach a ring terminal at this time. The ring terminal does not go under the washer, but against the nylon bolt head or the nut. Tighten the nuts finger tight. Repeat until all series connections have been made.  Check your battery packs voltage to be sure you got it right.

Provide Structural Support

Run ¼ inch threaded rods through the top tubes. Use nuts to secure. Do not use washers if installing inside a plastic fence post- they won’t fit. Do not over tighten threaded rod nuts, you might shear the tube off a BatteryBloc. Instead snug up the nuts and secure them with thread locker.  If building a power wall you can bolt the Blocs directly to a vertical surface and use side to side connectors.

Wire the Sensor and Power Wires.

Secure the sensor and power wires to the BatteryBlocs by crimping or soldering to the ring terminals. If you did not install the ring terminals while assembling the battery, just loosen the nuts and bolts to install.  Do not try to solder the power (large) ring terminals while attached to the battery. Crimp, or remove and then solder.

For help installing sensor wires see my video:  

How to wire a BMS

For wiring a battery without a BMS see:

How to build a better battery without a BMS

You would also connect the main power wires to the larger ring terminals at the positive and negative ends of the battery.

Tighten the nylon bolts.

Now that the battery has been properly wired tighten up the nylon bolts and steel nuts.  The official maximum torque for these nylon bolts is 19 foot lbs, but 15 is plenty. A Dewalt screw gun with an adjustable clutch makes short accurate work of it. Many people simply tighten by feel, it’s not critical.  The nylon bolts are somewhat elastic and the steel can flex a little.

Make two passes when tightening. Make the first pass with a light torque. Check to see that all the washers are laying flat against the Parallel Plate. If not, adjust with a flat blade screwdriver. Then make the second pass at full torque. This tightening will also twist the ring terminals. Realign them with a flat blade screwdriver.

When finished tightening, the cells should have zero up and down movement, but should be able to be rotated with friction.  Finally tighten up the threaded rod or mounting bolts.  Because the caps have a little wiggle room, tightening the threaded rod will not disturb the electrical connection.  Your battery pack should now be structurally quite rigid.

Install the BMS or the Hobby Charger wiring.

If you are not familiar with how to do this refer to the above videos or any of the many other Youtube videos.

Exploded 10 pack


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