When we tested the sample a few months ago we got 3.07mOhms and 19.8Ah @ 100A which was a very good result. It handled 100A with no worries for a good 12 minutes or so, until it hit 2.6V and was shut off automatically. [..] Charged accumulator to 410V (4.1V ea.). It balanced out well, managed an eventual delta of 0.005V after 1 day of balancing. Ran 35kW (5C) on the dyno today for a couple minutes, no problems, good temperature stability. Heaps of punch, very little voltage sag.
P.S. Your idea with the temperature sensors and the balance outputs on the LT chip worked a treat.Kyle Van Berendonck, Powertrain engineering. Team Swinburne, Australia
Li2x4p25R: Li-ion building block 3.6V/20Ah/18C
Build your battery in hours, not months.
Everything is taken care of, fully complies with FSAE regulations
Datasheet: Li2x4p25RT (revision K, 2016-10-19).pdf
This Li-ion building block was developed specifically for student electric formula competitions and with simplicity and safety in mind. Using 18650 lithium-ion technology, these building blocks offer the most modern and energy-dense solution in easy to use package. 18650 is a very well established and time-tested battery cell standard, especially common in consumer devices. These cells are designed to withstand consumer’s abuse, while offering the best in class energy density.
Various options of 18650 cell are available: SAMSUNG 25R, SONY VTC5, LG HE4 and almost any other genuine cell.
In addition to internal protection techniques, the module includes two fuses for each cell, 16 for entire 8-cell module. These act as a second level protection devices in case of cell failure and internal safety mechanisms being not enough.
In case of cell venting, released gas is travelled through dedicated channels to avoid pressure buildup.
Due to simple nature of these building blocks, desired battery pack configuration can be built in minutes, connecting them in series and parallel using bolt connections. Even MWh-scale batteries can be assembled with ease.
- Specially designed for FSAE 400V traction systems
- Small size: 271 Wh per liter
- Low weight: 172 Wh per kg
- Individually fuse-protected cells, no parallel fusing is required
- Ultra low self-discharge
- No initial balancing required
- Rapid prototyping of battery pack
- Convenient thermal control
- Built from genuine Samsung INR18650-25R cells
- Low flammability: UL 94 V-0 rated
- Nominal capacity: 20 Ah / 72 Wh
- Peak discharge current: 18 C max (360 A)
- Average discharge current: 10 C max (200 A)
- Nominal voltage: 3.60 V (2.50-4.20 V)
- Volume: 0.26 liter
- Weight: 427 g