Drop in lithium deep cycle replacement leisure batteries

Leaders in Lithium-iron Phosphate motorhome, caravan & marine leisure batteries

KS Energy UK Technology


So why us? - Lithium iron phosphate battery manufacturers share identical chemistries. Major differences emerge in fabrication quality and cell package design such as cylindrical, pouch and prismatic. When cells are assembled into a battery, further differences emerge in construction methods. In addition, safety, performance and lifespan are critically dependent on the design of the internal control system, the BMS (battery management system).

Construction quality

At KS Energy holdings UK, we prefer to keep the bar high. Yes it's always possible to build down to a budget, for example by using prismatic construction. Instead we choose to design and build to a standard. Using only cylindrical cells, specifically high quality 3270 calibre throughout our entire range. We do this for two reasons. Firstly, this lends itself to a manufacturing process that results in perfect electrical tolerance. Secondly, cylindrical stainless steel cell casing affords superior mechanical and electrical stability under variable temperature. The result is battery construction with exceptional uniformity and performance.

Internal view of a KS Energy Lithium Battery

Integral advanced BMS design


In its most basic form, a BMS ensures the battery capacity can be maintained during use. In recent years, BMS’s have evolved and now regarded as important factor of the battery. At KS Energy UK, we have innovated and incorporate some of the highest levels of features and specifications in the industry to maintain battery safety and performance, ensuring our batteries remain superior and are practically abuse proof.

Bluetooth 4.0 low power smart monitoring

All Super Series batteries incorporate ultra-low power Bluetooth monitoring. This displays real time Battery voltage, Charge and Discharge Current, Cell balance, temperature and Cycle count. In addition, a precise state of charge is calculated and displayed. 


Low temperature charge protection

Temperatures below freezing are common in British winter and normal charging then becomes catastrophic. We were among the first to integrate low temperature charge protection into our batteries. (An issue other manufacturers originally completely ignored or at best, glossed over). Our entire range of leisure batteries, from the 60Ah upwards incorporate this technology as standard.

BMS with Low temperature charge protection Click on picture above for more information

When lithium batteries are charged below freezing, lithium plating forms on the anode. This results in a permanent loss of cell capacity and an increased cell resistance. Also, cells no longer maintain their original safety integrity and become more susceptible to combustion under a fault condition such as shorting. Our Super Series range of batteries combat this by preventing charging when the temperature is dangerously low, yet allows normal discharging to continue. Where charging below freezing is an absolute necessity, we have the Arctic series which incorporate cell heaters to maintain cell temperature at a safe charge temperature, even under extreme conditions to -30 Celsius.

High current delivery and over temperature protection

Above our 100Ah range, we incorporate an additional transistor bank to allow the BMS to handle a continuous current of 150 amps without creating additional internal temperature and for safety, cell temperatures are continually monitored so that the current is automatically removed if safe working temperature is exceeded. This is a particularly desirable characteristic for those who require high power, for example inverters for off grid use or caravan users with motor-movers.

Overload and over voltage protection

Our BMS’s ensure complete safety of operation, shutting down if the load exceeds a safe limit, or a short circuit is detected, only resuming once the fault condition is removed. In a fault case where the charge voltage exceeds safe charge voltage levels, the BMS will switch the current off to prevent overcharging and overheating that would result in the risk of permanent cell damage.

Under voltage and cell balancing

Our BMS’s incorporate protection for over discharged cells which would otherwise result in permanent damage and cell capacity loss. When the battery reaches a pre-set discharge voltage, the battery will automatically switch off until it is recharged again. During normal use, cell banks must be perfectly balanced with equal states of charge otherwise battery capacity becomes permanently lost. Our BMS’s actively monitor and precisely balance each bank throughout every charge and discharge cycle. When the battery is not being used, the BMS will then enter a hibernation mode, drawing near zero current.

Safety Testing Certification and Warranty


The batteries are equipped with robust M8 bolts ring terminals and a detachable carry straps. (M6 for 60AH). The case materiel is 2.2mm ABS requiring no external ventilation. It is sealed to withstand water and dust ingress to a rating of IP56. We regularly perform independent quality and product testing including capacity cycling and safety testing to ensure our batteries continue to always meets original design specification.

Safety certifications

All our batteries are individually CE certified and tested to UN38.3 specification. This assures continuously meeting the requirements for product health, safety, and environmental standards in within the UK. It also ensures our battery cells are deemed safe to transport by land, sea, and air.

We were recently inspected by the Office for Product Safety and Standards to ensure our batteries complied with the current safety and standards legislation.

UN38.3 certified

Life span

KS Energy batteries have a very long life span and the user can expect upwards of 5000 cycles during normal use of an average of 70%-80% depth of discharge (figure 1.) which would be quite typical during normal leisure use. Therefore, we offer piece of mind with a 10 year warranty which we believe to be industry leading.

Even under the most abusive conditions our battery cells show that a lifespan exceeding 2000 cycles is easily achieved where the depth of discharge is abnormally deeply cycled from fully charged to fully discharged and back at a high load current of 0.5C. After which the battery still maintains a very usable serviceable capacity exceeding 70%.

Left unchecked, the self discharge of the battery (figure 2.) averages just few percent per month and there is no need to float charge the batteries or recharge them again during periods such as over winter (providing there is no external drain source such as tracking devices/alarms, clocks etc.) A service charge cycle is only recommended in cases exceeding 9 months.

Figure 1.
Figure 2.

Please note we are aware of a far eastern company (GSL energy) labelling batteries under our registered brand KS Energy. KS Energy Holdings (UK) Ltd is not connected with this manufacturer and we expressly do not endorse its products which we have seen, tested, and found of substandard capacity and quality of assembly.  Please ensure you are obtaining genuine KS Energy holdings (UK) designed and manufactured batteries by obtaining them either directly from us or through our authorised retailers. KS Energy and the battery logo are registered trademark under registration UK0000342424042. The use of our name and logo is strictly prohibited without the express written agreement of KS Energy Holdings (UK) Limited. Apple and Android logos are registered trade mark of Apple and Google respectively.