# SOH Estimator

**Libraries:**

Simscape /
Battery /
BMS /
Estimators

## Description

This block implements an estimator that calculates the state of health (SOH) of a battery. The SOH reflects the condition of a battery relative to its ideal conditions. Health variations imply that the capacity and power of the battery fade over time.

This block supports single-precision and double-precision floating-point simulation.

**Note**

To enable single-precision floating-point simulation, the data type of all inputs and
parameters must be `single`

.

This diagram shows the structure of the block:

### Equations

The terminal resistance *R*_{0} is an important
indicator of the aging of a battery. You can estimate the terminal resistance by
using the SOC Estimator
(Adaptive Kalman Filter) block. The SOH Estimator block
computes the SOH as a function of the terminal resistance
*R*_{0}:

$$SOH=\frac{{R}_{\text{EOL}}-{R}_{0}}{{R}_{\text{EOL}}-{R}_{0,\text{new}}}$$

where *R*_{EOL} is the
end-of-life resistance and *R*_{0,new} is the
terminal resistance when the battery is new.

## Ports

### Input

### Output

## Parameters

## References

[1] Noura, Nassim, Loïc Boulon, and
Samir Jemeï. “A Review of Battery State of Health Estimation Methods: Hybrid Electric
Vehicle Challenges.” *World Electric Vehicle Journal* 11, no. 4
(October 16, 2020): 66. https://doi.org/10.3390/wevj11040066.

## Extended Capabilities

## Version History

**Introduced in R2022b**