So, der Chef hat mal paar Fragen beantwortet:
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Some questions are fair enough and we definitely welcome engagement with potential clients.
Some show that people don’t entirely understand the tech and some relate to proprietary info, so I will answer what I can.
One user is asking, if some charts are available and could be shared
We spent a lot of time researching and testing cells to ensure we get optimal performance - I’m sure you can appreciate that we can’t give away the exact model of the cells. Furthermore, we are not cell manufacturer, but rest assured, we use cells by A123 Systems which are some of the best in the business. You might know a really expensive German brand also using A123 System cells.
Questions about the BMS
- Short-circuit test: Battery (+ -) short-circuited - Battery management system (BMS) cut off
- Rapid discharge test: Fast discharge (2C - discharge of full capacity in 30min) - Battery management system (BMS) cut off when the voltage reaches 8V to prevent overdrain
- Rapid charge test: Rapid overcharge (sustained 2C charge) - Battery management system (BMS) cut off when the voltage reaches 15.6V to prevent overcharging
Recovery strategy following any of the above protection modes, cells can be woken and reinitiated via Deadweight Industries rapid charger.
How long can a deeply discharged battery be stored?
If disconnected from drain, at partial charge level, our batteries will sit easily 6 to 12 months with minimal self drain.
I’m unsure why anyone want to completely flatten their battery and then put it into long term storage. The cells won’t like that… in fact, no battery can withstand this - lead acid, gel, AGM.
What maximum permanent charging voltage can the BMS and the battery itself withstand ?
A good alternator should put out between 13.5-14.5 volts - which our batteries are obviously designed for.
LiFePO4 don’t like at all to be permanently stored empty or full.
Correct - hence parameters in the BMS are set to minimise such incidents.
You say the BMS can manage any alternator from automotive, but how come it is generally suggested to use only LiFePO4 charging devices only?
Lead-acid charger have a charge phase called the “float” stage. Which is low amps constantly being forced into the battery to keep it topped up. Great for lead-acid, terrible for LiFePO4.
Alternator output based on draw of the systems in the car (including battery). Our battery will only draw what it needs.
NVH on the S2000 is very strong - can this lead to breakage of these soldered connections à short circuit
Our batteries are UN38.3 certified - and meet standards for transported by air.
Part of the certification is a multi-axis vibration test to ensure the battery and connections are structurally sound
Furthermore - we would only recommend using LiFePO4 batteries that is protected by a FULL BMS - not just a balancer.
The short circuit protecting is there to provide a secondary fail safe.
Motorsport Association UK approved for racing in the UK (I know this might not mean much for Germans!)
I will close by saying, we are passionate Nürburgring and track enthusiasts ourselves who take a lot of pride in our own cars, so we understand that people want the best.
Our product has been out there in the community for a long time, and we’ve had overwhelmingly positive customer feedback.
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https://www.deadweightindustries.co.uk/blogs/news/lig…ting-conditions
Ich lasse die Umfrage mal so stehen. Vielleicht kriegen wir ja 5 Leute zusammen.
