Varley Red Top Racing Battery

Does anyone have experience with these batteries? They are super lightweight (e.g., just 6-9Kg depending on size) and said to be the best batteries out there. Pricey though.
According to their website:

Main Benefits

Aircraft derived technology
Excellent high discharge performance
No topping up or maintenance is required
Sealed construction - no electrolyte leakage (even if outer case is damaged)
Lightweight
Can be fitted upright or on their side
Can be stored up to 24 months before use, from full state of charge
Applications include:-

Rally Cars
Classic Cars
Microlite Aircraft
Robotics

FAQs

For Sealed Lead Acid, Pure Lead and AGM Batteries.

Can I fit my battery on its side?
YES - The battery can be installed in any orientation (although inverted is not recommended)


How can small batteries give as much power
as large conventional batteries?
Sealed lead acid batteries from DMS technologies are designed using pure lead tin technology, developed for aviation use with thin lead plates to give low internal resistance and exceptional high rate performance.

Should I discharge my battery with a bulb to
Reduce Memory Effect?
NO. Pure lead technology does not suffer from Memory Effect and may be damaged by this action. Pure lead batteries should not be left in a discharged state but recharged ASAP.

Will the battery leak acid if it is broken?
NO- the electrolyte is contained within an absorbent separator inside the battery.


Do I need to top the battery up with distilled
water?
NO- no access is available into the battery and maintenance is not required with this technology.


What are the common causes of battery failure? Incorrect charging, over discharge and wrong application.


Can the batteries be used in extreme temperature
conditions?
YES. Some of the battery technologies can be installed in temperatures ranging from -65°C to + 80°C

What determines the life of a battery?
The life of the battery in a cyclic application is generally determined by temperature, depth of discharge and rate of discharge. For float applications the life is determined by ambient temperature, number of discharges and charge level.

Are the batteries safe to be transported
by air?
Most of our battery technologies are declared non-hazardous for air transportation, however, there are some exceptions.

Can the batteries be fitted into hermetically
sealed enclosures?
Batteries must not be recharged in sealed enclosures as this can cause an extreme hazard. It is possible however, to fit a vent which can eliminate this limitation.

Can DMS offer designs in different battery
technologies?
Yes, DMS has years of experience with different battery technologies and offers advice on design.


What is the difference between AGM and Gel
technologies?
An AGM battery is constructed using Absorbent Glass Mat between the lead positive and negative plates in which the liquid electrolyte is suspended, thus producing a battery with no free acid.
A gel battery is more similar to a conventional battery however it has a gel added to the electrolyte to limit its movement.



What is the difference between float and
cyclic applications?
A float application is typically where the battery is constantly on charge with the occasional discharge ie. UPS and telecommunications.
A cyclic application is where the battery is discharged and recharged (one cycle) on a regular basis.

 

Thanks, I'll ring them tomorrow. I wonder if it's the same construction.