Updated: Mar 16
When the warnings such as the dreaded master warning triangle, check hybrid, ABS (anti - lock brake system) and VSC (vehicle stability control) ECB Electronically controlled brake, engine management light and check hybrid system are triggered on your Toyota or Lexus, hybrid/electric vehicle, it can be by as little as a few bad modules in the entire high voltage battery when all the others are still going strong. In many hybrid vehicles such as Toyota Prius or Lexus GS450H each NiMH module contain 6 individual cells, these modules are connected by bus bars in series configuration. Each modules nominal voltage is 7.2 volts (6 x 1.2 volt cells) In a Toyota Prius there are a total of 28 modules so in total 168 cells, where as in the Lexus GS450H there are 40 modules so 240 cells.
At Hybrid Repair Service all replacement modules are load tested and tested for capacity to ensure they are suitable for the job. New modules are available but it is not advisable to fit single brand new modules in older high voltage batteries as they will not work so well in balance with older module/cells.
Another factor can be the oxidation of the copper bus bars, the copper links which connect the modules within the battery in series. This is not problem you are going to run in to on a brand new models, but on older models like generations 1, 2 and 3 Toyota Prius, most certainly. Over time, corrosion can inhibit the connections within the battery's ability to conduct electricity, reducing battery efficiency and in turn make for worse fuel economy and in the very worst cases could be at the very least, a contributory factor in battery warnings.
Nickel plated bus bar are available, which works well to combat corrosion and although Nickel is only 7% conductive there is a thin coating of Nickel to 99.9% pure Copper, they have been seen to improve fuel economy is some vehicles when fitted.
Another option is to have a brand new complete replacement wiring harness including new copper bus bars.
So in short, there are many options available when it comes to servicing your battery, to make sure you get the most life from your hybrids high voltage battery.
At Hybrid Repair Service every single bus bar (connection between module/cells) are changed for anti corrosion nickel plated ones, where possible even with our, top quality, low price repairs. For details of our services, Please contact Mark @ Hybrid Repair Service for more information using the contact details at the bottom of the page.
It is possible to have NiMH technology batteries reconditioned, putting them through a process to regain lost capacity. This process breaks down the dendrites (crystalline structures which forms in the inside battery modules) thus, improving battery performance and fuel economy.