Do It Yourself
​
Benefits: Save money and turn it into a fun project with hands-on experience.
​
Requirements: To do this job properly, you must invest time in research and some basic equipment. You also need to be able to afford the downtime of your car. Additionally, don’t forget to buy at least two (if you're lucky) or more (if you're unlucky) failed battery packs with the same modules for use as donors.
​
Risks: You're dealing with a high-voltage DC system, which can be lethal if mishandled; however, the risk is minimal if you know what you're doing.
​
Limitations:
​
-
Equipment accuracy and amperage rating: If you're doing this to save costs, the equipment you invest in will be limited to certain amperage ratings. In the real world, hybrid batteries operate at high amperages. Often, the testing data collected by most off-the-shelf RC chargers/dischargers is not applicable or comparable.
-
NiMH self-discharge: While many RC chargers offer up to 4 testing channels (costing hundreds of dollars), batteries typically consist of 20-40 modules. With testing cycles lasting hours or even a full day, achieving a reasonably balanced battery pack can be challenging.
Conclusion: Treat it as a fun project—set aside plenty of time, do a lot of research, take all necessary safety precautions, manage your expectations, and enjoy the process. If you get it right with some luck, congratulations.