Drop in lithium deep cycle replacement leisure batteries

Leaders in Lithium-ion Phosphate motor home & marine leisure batteries

12V Lithium-ion Phosphate Leisure Battery Technology


LiFePo cell chemistry is the perfect balance between size, weight, energy density and life span. Various formats exist such as prismatic and pouch but for physical and electrical robustness not to mention longevity of life, we prefer to employ cylindrical cells in our batteries, which are conditioned and matched prior to assembly. Take a look at some of the videos of the superior construction and the electrical performance of our batteries. Superior to lead based chemistry, our batteries return almost all stored energy at a constant voltage. This makes them the perfect choice for leisure use, especially when reliable off grid power is required to meet demands from lighting, televisions, inverters, even ovens. We use a range of manufacturers for our OEM products. In order to achieve very high quality, this includes specifying, designing and sometimes local (UK) based manufacturing. We also have a range of dedicated chargers and associated electrical accessories.

  • LCD LiFePo battery meter
    Battery voltage and capacity meter plus temperature
  • KS-HT120 bluetooth lithium battery
    Internal view KS-HT120 Super Series bluetooth battery
  • Power terminal
    F12 Power terminal lug (M8 bolt)
  • KS-ARC100 battery
    Inside KS-ARC100 Arctic series heated battery
  • Lithium phosphate LCD battery meter
    LCD voltage meter
  • Manufacturing line KS-HT120
    Manufacturing line KS-HT120 battery
  • Lithium lesiure battery model KS-LT100
    Internal view KS-LT100 Super Series battery

Since charging lithium at low temperatures cause irreversible damage. Our Super Series High power series now incorporate low temperature charge protection as standard.

In addition, for cold environments, we have designed our "Arctic Series" which feature integral heating elements, allowing normal charge and discharging throughout sub zero winters.

Any battery (Excluding Bluetooth models) can be supplied  with an integral LCD voltage/temperature meter. All batteries have integral advanced battery management systems, robust F12 (M8 bolts) terminals and a detachable carry strap.

KS-KT100 Batt Instruction Guide.pdf


All our batteries have short circuit and over temperature protection (The Super Series have low temperature charge cut out protection). They do  not contain dangerous acids or produce flammable gasses, all of which lead based batteries do! Lithium batteries have had a little bad press with fires in mobile phones, hover-boards and Boeing's Dreamliner springing to mind. However these are all lithium-polymer batteries.  A very different battery cell to what we use (LiFePo4). These have a wide charge and discharge tolerance. Under severe stress conditions such as over charging or shorting, ion exchange creates lower intrinsic heat and thermal runaway is then almost impossible.

UN38.3 certified (Land, Sea, Aviation)

This means fire risk is highly unlikely, moreover there's no production of explosive gas.  Our batteries are CE certified and tested to UN38.3 specification. This assures we not only meet, but exceed the requirements for product health, safety and environmental standards in the UK. We were also recently inspected by the Office for Product Safety and Standards to ensure our batteries complied with the current safety and standards legislation.


KS Energy batteries are priced at a point where lifespan ( >5000 cycles @80% - 30% DOD 0.5C, >2500 cycles DOD 95% 1C), energy density, weight and safety trounces all conventional lead technologies. Lithium-ion phosphate (developed in 1996) is becoming the choice of battery chemistry replacing lead (Pb) acid battery formats, including GEL and AGM. LiFePo4 has around four times usable energy density to Pb. Due to the entire charge being available at a usuable voltage, it is often said to be twice as efficient as a like rated lead acid battery. This means that at 100Wh/Kg it can result in physical weight savings of around four times, crucially reducing axle weight and allowing increased stowage.


  KS Energy batteries come with an industry leading guarantee. Under normal use, the usable lifespan of our leisure batteries offer a typical cycle life of 5000 cycles (80% - 30% DOD @0.15C discharge) which would be in excess of 15 years daily use.

Stability: Our batteries are normally constructed from type 26650 or 32700 3.2V Lithium-ion Phosphate cylindrical matched cells which are packaged in sealed stainless steel. Between each cell group we integrate a unique cell management system. Our integrated cell management system ensures each cell always functions at its optimum, both during charge and discharge. Unfortunately without cutting a battery open, it is difficult to access its quality. Many inferior or cheaper batteries will be constructed from Prismatic cells, which are not as mechanically or electrically stable. Especially when used to extremes over time. For this reason, at KS Energy we prefer to incorporate cylindrical cells.

Life:  These batteries are among the longest lived and safest batteries ever developed. Test data in the laboratory points to well in excess of 5000 cycles from 80 to 30% and over 3000 from 80% to 0% charge/discharge cycles. This is due to the extremely robust crystal structure of the iron phosphate, which does not break down under repeated packing and unpacking of the lithium ions during charging and discharging including fast forced charging. Shallower cycles result in numbers approaching 4000 cycles (in excess of 10 years serviceable life.

Energy Density: This technology not only has a very high energy density but delivers high power for longer. Lithium cells can supply power to near zero capacity before cell voltage significantly tails off This means they can deliver nearly 100% of their stored energy. Moreover Lithium cells are perfectly happy operating in this way. Conventional Pb batteries suffer sever degradation once around 50% of the power has been delivered and significantly shortened life spans (<30 cycles typical), even worse cell voltage tails off meaning the stored energy is never practically accessible. For this reason a 100AH rated lithium battery may often be regarded as the equivalent of a 200AH lead acid battery!

Environmental Impact: KS Energy only manufacture LiFePo4 batteries and our batteries have dramatically reduced environmental impacts. Compared to lead battery chemistry, there is no highly toxic and environmental contaminating lead. The chemical elements in our batteries simply become inert upon recycling. Moreover the useful working life span can be more than 8 times that of a lead acid battery so that the ongoing carbon foot print of manufacturing reduces like for like

Simplified Charging: In addition, since cell voltage tolerance is wider and impedance lower, LiFePo batteries can accept a higher constant current charge resulting in faster charge times and since internal discharge minute, there is no requirement for trickle charging either. All KS Energy batteries incorporate cutting edge individual cell management circuit boards with LCD (optional blue tooth) charge control indicator. We are also among a few manufacturers  who have given any consideration to low temperature charge protection, offering a range of batteries (Super Series) that automatically incorporate this safety feature.

JS-C33 LCD Battery Meter.pdf