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Care tips for Li-Ion hybrid battery

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Post by Admin Sun Apr 20, 2014 8:18 am

How to derive maximum benefits from hybrid tech?

The concept of hybrid tech is that it stores energy that would otherwise be wasted, for later use.  Energy is stored from coasting (minimal) and braking (maximum).  The best use of this stored energy would be in stop go situations, idle situations, gliding and short paces.  In short, where usage of engine power, due to low gearing and stationary situations results in the highest or wasted fuel consumption.

Understanding that, hybrid is not a cure all for all driving situations when at most times, engine power provides the best driving efficiency in normal driving conditions where more power is needed.  Therefore, forcing EV mode all the time is actually a strain on the components and an enemy of efficiency since engine power will later be needed to restore charge (and not charged from wasted energy ie coasting or braking)

Therefore, it is given that the most efficient way to charge the vehicle is via coasting and braking while the best use of this stored energy is in idle or stop go situations.  So, drive normally as you would in normal conditions but whenever possible, anticipate traffic ahead so that you can coast and/or better still, progressively brake far before a stop (to invoke regen charging)

What I usually do is that, I have the histogram graphs on my MMI whilst having the hybrid car graphic on the dash display cockpit.  The histogram will show me whether I'm efficiently recharging the battery packs.  If the yellow graph is high and correspondingly, green bar is high too, it means I'm using engine power to recharge - that is not efficient

What you want to achieve is for lower orange bars whilst a longer green bar.  That will show that regen energy is stored most efficiently from coasting and braking (not engine and thus, this most efficient use of wasted energy)

The small car graphic on the dash cockpit will aid me when I want to feather the throttle light enough to move ahead (without engine power) or if I want to glide.  The graphic will tell me that I've feathered the throttle too hard and thus, invoking engine power instead which in this case, I release the throttle and start again.

I've glided at 120kmh for a considerable distance (depending level of stored energy) using exclusively battery power alone with this technique


Posts : 186
Join date : 2013-06-25

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Post by Admin Sun Apr 20, 2014 7:55 am

Hi bro papaaz

I've passionately researched on this topic too before and during my ownership of the A6h to derive maximum benefits and enjoyment from the hybrid tech.

In general,
- yes, Li On is more efficient (minimal memory effect), packs greater density and lighter than NiMH which although suffers from the above shortfall is regarded as more durable, less volatile and proven than the former since they have been used in Prius-es in US as taxis for nearly 10 years with nary an account for a replacement unless abused.
- hybrid battery packs are expected to last a life time of the car. 300k km is conservative estimate as highlighted, Prius taxis in the US has been running for nearly 10 years with hardly any immediate need for replacement. Mitsubishi president, when launching the I-Miev says the LiOn battery in the car should still retain at least 70% efficiency even after 10 years of operation. This shows the maturity of the tech.
- in what was considered a smart move, Audi trained the air conditioning ducting to actively cool the hybrid battery pack extending their efficiency and lifespan besides the standard ECU controlled active monitoring
- it is true that LiON batteries should be drained completely nor overcharged to preserve their lifespan. This is why modern smartphones with LiON battery packs are not encouraged to be charged overnight.
- in the case of a6h, even if the meter shows a complete discharge, there will still be reserve capacity to prevent complete drain plus the engine kicking in when the ECU sensors such
- anyway, with this knowledge that LiOn should not be completely discharged to maintain its lifespan, we can now invoke the engine to kick in when we see one or two bars left rather than expensing it dry.


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Post by PapaaZ Sat Apr 19, 2014 10:47 am

Arising from Admin bro valueable advices on not to engage EV mode except under certain circumstances (Thank you Sir Admin, under topic : Latest fuel consumption), I went on checking and realised that there are differences between Li-Ion hybrid battery (A6H) & NiMh (like Prius) from web references (google “care tips for Li-Ion hybrid battery”), and it seems that:

1) Li-Ion is preferred for hybrid car compare with NiMh nowadays.
2) Li-Ion battery should last 300,000 km under good care, if one travel 30 kkm a year, it should last 10 years in theory.
3) Li-Ion battery suffers under excess heat operation.
4) During charging, Li-Ion battery require constant temperature, thus the car air cond ducting extended to the battery for A6H. Charging under high temperature would shorten its life.
5) The shorter the discharge (use the battery power & charge the power level up again), the longer the battery will last, namely it is good to practice partial charge cycle. Does it means we maintain battery power level at middle level + & - 2 to 3 bars?
6) Avoid completely discharge, although ECU has a protection control. Does it means when the battery level left with a bar, then we should shift to Sport mode for recharging, or else battery life shortens?
7) On the other hand, avoid charge it to max. This is alright, it is not ease to charge A6H battery to max level anyway.

Any other valuable advice that may keep our hybrid car battery last longer?


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Join date : 2013-10-22

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