Once again the summer heat made the battery production facility inhumanely hot for factory work and production (a.k.a. the garage). That coupled with added parallel workload left the innovation division largely stalled for Q1, Q2, and Q3 of 2021. However, a build was finally produced.
The DenCo Batt Mk IX uses a Daly BMS rated at 20A. It is different from other BMS’s used due to its common-port charge/discharge configuration. Despite being common-port, this battery still has a separate charging input with a 5.5×2.1mm barrel jack.
This battery uses the remaining LiitoKala 6.5Ah cells in DenCo stock. It incorporates the patented famous USB and voltmeter additions, and has ample protective backing and neoprene cushioning on the bottom.
Created: September 12, 2021.
Cells: LiitoKala 32700 “7Ah” (actually around 6.5Ah) 3.2v LiFePO4.
BMS: Daly LEP-4S 20A enclosed common-port BMS.
New since last make: New BMS.
Current Owner: K5YVY Brett
LiitoKala 32700 cells
Nominal Capacity: 7Ah (6.5Ah in practical use)
Nominal Voltage: 3.2V per cell
Dimensions: 32mm x 70 mm
Weight: 145g per cell
Internal resistance: less than 8 mΩ
Cycle life: > 2000 cycles, DOD at 80%
Input charging voltage: 3.65v/cell
Input charging current: 3A
Continuous discharge current: 30A
Max discharge current (pulse): 6C
Discharge cut-off voltage: 2.5V
Charging temp: 0-45°C
Discharge temp: -20°C – 60°C
Storage temp: -20°C – 45°C
Daly LEP-4S 20A Common Port BMS
4 series 3.2V LiFePO4 batteries only.
Size: 58mm x 33.5mm x 7.5mm (actual measured).
Discharge continuous current (max): 20A
Pulse max current: 60A +/- 10A
Internal Resistance: <= 20µΩ
Charge voltage: 14.6V
Charge current: 10A
Over charge detect voltage: 3.75V±0.05V
Over charge protection delay: 1 second
Over charge release voltage: 3.55V±0.05V
Balance voltage: 3.5V
Balance release voltage: 3.5V
Over discharge detect voltage: 2.2V±0.05V
Over discharge detect delay: 1 second
Over discharge release voltage: 2.7V±0.05V
Over current delay: 1ms
Over current release condition: Remove load
Short circuit protection condition: External short circuit
Short circuit detection delay: 250 µS
Short circuit protection release condition: Remove load
Temperature protection: N/A
Self consumption: 100 µA.
Sleeping current (when in discharge): 0
Working temperature range: -20C to 70C
Storage temperature range: -40C to 80C