loamoaf
Active Member
- Region
- USA
Nice work on the battery pack, lower profile than my 4p and I really need to swap my clear shrink or polyolefin. 0.2mm nickel is plenty if 30A is max pack draw and looks like you managed to get 3 connections between each series group so no hot spots. I welded with 0.1mm nickel strip on top of 5 mil copper sheet at around 68J with my kWeld - both nickel and copper bonded to the cell and would rip the sheet before the welds. I was concerned using copper initially especially being coastal and in a humid area, but I grabbed some MG Chemicals acrylic conformal coating and potted the ends of my cells and all the connection - my cell holders are printed in a way that each group connection is down in a little cup or pocket to isolate the metal. I only have enough space to maybe squeeze 15 cells in a row but that makes it tight, so mine is just arranged in 4x14
I also swapped both my stock M620 and X1 power cables for 10awg + XT90 from the board to the connector. Mueller Electric coolflex 45 has a thinner jacket than other high strand 10awg silicone cables - still a little thicker than the 12awg but still can fit through the motor grommet. This also gave me maybe another 8" of power cable and eliminated the APP45 connection in there. Unfortunately seems like my X1 shipped with a faulty speed sensor
Some extra notes are to use some EC5 bullets between the BMS and battery/connector - just in case you need to replace or disconnect to prevent parasitic draw makes it much easier. I printed plates that interlock with my cell holders so that the pack uses the stock battery retention lock. I also use a velcro strap like you for backup but it's been nice and secure for 232km so far. I'm using Lishen LR2170SF cells - 4500mAh and 13.5A, pack charges 901Wh at 5A from my Satiator.
BAK makes some really good 5000mAh 21700's that are second only to Samsung 50S in terms of energy delivery at higher power outputs. I get about 50 miles of riding before I'm down to nominal resting voltage.
I have the clearance where I'd like to slap a layer of neoprene and mylar under the heat shrink for a insulating layer in the winter months, but I'm also looking into an externally powered self regulating PTC thin film heating solution to build into my second pack, something that can pull like 3-5W to maintain a 60°F maximum on the heating elements, 3 of them squeezed between each parallel series in the pack. So far though the Lishens only sagged maybe 1V total for the pack in 38°F rides so who knows. Pack hardly gets above ambient temperature even drawing 1200W
I also swapped both my stock M620 and X1 power cables for 10awg + XT90 from the board to the connector. Mueller Electric coolflex 45 has a thinner jacket than other high strand 10awg silicone cables - still a little thicker than the 12awg but still can fit through the motor grommet. This also gave me maybe another 8" of power cable and eliminated the APP45 connection in there. Unfortunately seems like my X1 shipped with a faulty speed sensor
Some extra notes are to use some EC5 bullets between the BMS and battery/connector - just in case you need to replace or disconnect to prevent parasitic draw makes it much easier. I printed plates that interlock with my cell holders so that the pack uses the stock battery retention lock. I also use a velcro strap like you for backup but it's been nice and secure for 232km so far. I'm using Lishen LR2170SF cells - 4500mAh and 13.5A, pack charges 901Wh at 5A from my Satiator.
BAK makes some really good 5000mAh 21700's that are second only to Samsung 50S in terms of energy delivery at higher power outputs. I get about 50 miles of riding before I'm down to nominal resting voltage.
I have the clearance where I'd like to slap a layer of neoprene and mylar under the heat shrink for a insulating layer in the winter months, but I'm also looking into an externally powered self regulating PTC thin film heating solution to build into my second pack, something that can pull like 3-5W to maintain a 60°F maximum on the heating elements, 3 of them squeezed between each parallel series in the pack. So far though the Lishens only sagged maybe 1V total for the pack in 38°F rides so who knows. Pack hardly gets above ambient temperature even drawing 1200W
