Design and Implementation of On-board Electrical Power ... - OUFTI-1

of the batteries is kept between -22 ◦ C and +37 ◦ C [7]. The batteries will be maintained above0 ◦ C by a 500mW heater. According to Fig. 3.20, a beneficial side effect of the heater is tokeep the batteries capacity beyond 1,100mAh.Figure 3.20: Variation of voltage of KOKAM SLPB554374H during discharge for severaltemperatures [20].The batteries have been successfully tested in vacuum by Philippe Ledent.3.4 Battery protection circuitsThe KOKAM batteries are delivered with a protection circuit module (PCM). The role of thePCM is to protect the batteries against over-charge, over-discharge and over-currents. Thesemodules are directly soldered on the batteries terminals. Each battery has its own PCM.The choice can be made to keep that circuit or to make our own. Our first choice was touse the protection circuits of the manufacturer (KOKAM).The operating temperature range of the KOKAM PCM is -10 ◦ C to 50 ◦ C and the storagetemperature range of the KOKAM PCM is -20 ◦ C to 60 ◦ C. Given that the PCM is in directcontact with the batteries, and that the temperature of the batteries is maintained between0 ◦ C and 45 ◦ C, the temperature of the PCM is expected to stay in a good range.The schematics of the KOKAM PCM is shown on figure 3.21.3.4.1 Electrical characteristicThe electrical charateristics are shown in the table 3.4.34