03-25-2019, 09:58 PM
Yeah, as said, a Battery Management System. The LiFePo4 battery I suggest comes as a sealed package with a couple of terminals on top. That is all a dummy needs to get at in use.
A BMS stops over charging and over discharging. Essentially, safety for the battery. Peoples building their own battery will usually decide what voltage will be "full" and what voltage will be "flat" and then take care to ensure the charger does not charge to too high a voltage and they also put in some electronic thingy as a Low Voltage Cutoff to stop the discharge from going so low as to damage the battery. Really clever people trying to get the absolute most out of their DIY set up also put some more electronic magic in there to "balance" the individual cells. Balance is all about making sure all the individual cells in the battery are at the same voltage level. If one cell is higher in voltage than the rest, the high cell in the battery pack will try to start charging the low cell in the battery pack. The other need for balance is so that one cell does not go lower than the others to the point where the individual cell is damaged. People in the EV world mostly concern themselves with a top balance and RV folk mostly concern themselves with bottom balance. EV folk want their battery packs as full as possible when they take the vehicle off charge to go for a drive, while RV folk want to keep the fridge cold as long as possible. Batteries best for self categorised dummies are those where the battery manufacturer has made all the decisions about what voltage the battery should get to when full and how low to go when you want it to produce power for as long as possible. Hence my suggestion that a battery for a dummy should be one that comes with an integral BMS.
A BMS stops over charging and over discharging. Essentially, safety for the battery. Peoples building their own battery will usually decide what voltage will be "full" and what voltage will be "flat" and then take care to ensure the charger does not charge to too high a voltage and they also put in some electronic thingy as a Low Voltage Cutoff to stop the discharge from going so low as to damage the battery. Really clever people trying to get the absolute most out of their DIY set up also put some more electronic magic in there to "balance" the individual cells. Balance is all about making sure all the individual cells in the battery are at the same voltage level. If one cell is higher in voltage than the rest, the high cell in the battery pack will try to start charging the low cell in the battery pack. The other need for balance is so that one cell does not go lower than the others to the point where the individual cell is damaged. People in the EV world mostly concern themselves with a top balance and RV folk mostly concern themselves with bottom balance. EV folk want their battery packs as full as possible when they take the vehicle off charge to go for a drive, while RV folk want to keep the fridge cold as long as possible. Batteries best for self categorised dummies are those where the battery manufacturer has made all the decisions about what voltage the battery should get to when full and how low to go when you want it to produce power for as long as possible. Hence my suggestion that a battery for a dummy should be one that comes with an integral BMS.
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