Nissan LEAF 40kWh Lithium Battery Controller (LBC) a.k.a. Battery Management System (BMS)

This LBC / BMS is a brand new new genuine Nissan product. Its original application is on the ZE1 LEAF with 40kWh battery and WITHOUT the battery heating system used in some parts of the world such as Canada and Scandinavian countries. As it is a new product, all learned parameters are on the default values including the State of Health being 100% with 12 bars shown on the instrument cluster.

This product can be used as a replacement for a faulty LBC, but another common application is when rebuilding a degraded 24kWh or 30kWh LEAF battery pack using new 1670Wh modules as used in the 40kWh pack. In this situation, the original LBC will not function correctly as the new modules are way outside of the normal parameters that can be learned over time. Additionally, the balancing circuit in the 24kWh and 30kWh LBC hardware has proven to be inadequate when used with larger cell capacities and this can lead to a large imbalance in individual cell voltages over time. The 40kWh and 62kWh LBCs in comparison have much stronger balancing capabilities.

In the case of a battery pack rebuild, the matching current sensor must also be used as the calibration and number of signals (two for redundancy vs one) is considerably different between the 40kWh LBC and the earlier LBCs used in the 24kWh and 30kWh packs.

With the right replacement terminals and crimping tools, a skilled auto electrician can modify the original wiring loom to accommodate the new current sensor, but the easiest option is to purchase this loom separately as it isn’t large or unreasonably priced.

Finally, to make this LBC function with an earlier vehicle, we recommend one of our battery translator kits just as we would with a factory built 40kWh LEAF battery pack.

High voltage battery pack rebuilding is a hazardous activity that brings real risks of fire and/or electrocution which can lead to injury and death. We recommend that this activity is only performed by experienced people who thoroughly understand these risks and how to safely manage them.