Battery Equivalents and Replacements

ExpertPower EP12100 12V 100Ah Lithium LiFePO4 Deep Cycle Battery

ExpertPower EP12100 is an ultralight Lithium Iron Phosphate (LiFePO4) deep cycle battery, that offers great weight savings and a much larger number of charging and discharging cycles when compared with lead-acid batteries.

Since the ExpertPower EP12100 is a lithium battery, it also features an initial higher price, and it is more sensitive to charging and discharging conditions than lead-acid batteries. Nonetheless, ExpertPower EP12100 is one of the most popular lithium batteries in its class.

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ExpertPower EP12100 Features and Specifications

ExpertPower EP12100 physical dimensions are (L x W x H) 13 x 6.8 x 8.4/9.3 inches (~330 x 173 x 214/236 mm) and it weighs only 22.6 pounds (~10.3 kg), which is on average just 1/3 of the weight of the typical BCI Group 31 100Ah battery.

ExpertPower EP12100 features a nominal voltage of 12.8 volts and its voltage stays above 12V up to 90% DoD of the battery - it has a much flatter voltage curve than lead-acid batteries.

The nominal capacity of the ExpertPower EP12100 battery is 100 Ah when the battery is discharged at 0.2C rate (20 Amps) for 5 hours.

ExpertPower EP12100 battery comes with F12/M8 terminals, allowing the user to firmly connected power cables with the minimum energy losses.

The maximum continuous discharge current is 70 Amps, with the maximum discharge current of 100 Amps for 10 seconds.

According to the manufacturer, the maximum continuous charge current is 50 Amps. IMHO, charging current in the 0.2-0.25C (20-25 Amps) range is much better in order to avoid overheating and other potential problems with the battery.

The charging voltage is 14.4±0.2V - ExpertPower EP12100 should be charged using battery chargers intended for lithium-ion batteries or with the battery chargers that have a special lithium-ion battery charging mode - preferably one that uses a 2-stage constant current/constant voltage (CC/CV) charge algorithm, like ExpertPower EPC1220 12V 20A Smart Lithium Battery Charger (Amazon link, link opens in the new window).

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Fully discharged ExpertPower EP12100 may be recharged fully using ExpertPower EPC1220 in slightly more than 5 hours.

Other lithium-ion battery chargers may also be used, but the lithium battery ExpertPower EPC1220 charger is optimized for ExpertPower lithium-ion batteries and it costs only a fraction of the battery cost - if You decide to buy an ExpertPower EP12100 battery, ExpertPower EPC1220 is highly recommended.

ExpertPower EP12100 features a built-in Battery Management System (BMS) which protects the battery from critical events like overcharge, over-discharge, overloading, overheating, and short circuit.

The battery itself also features a very low self-discharge rate of less than 2% per month (at 77°F, 25°C), ensuring up to 1-year maintenance-free storage. After one year of storage, fully charged ExpertPower EP12100 will drop down to 76% of full charge, with no adverse effects on the battery.

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ExpertPower EP12100: Number of Charging/Discharging Cycles

One of the great advantages of the ExpertPower EP12100 is its lightweight design - just a fraction (~1/3) of the lead-acid battery weight.

Another advantage is a much larger number of charging/discharging cycles that the battery is able to withstand:

- down to 100% DoD: 2500 cycles,

- down to 80% DoD: 3600 cycles,

- down to 50% DoD: 7000 cycles.

AGM/Gel-Cell lead-acid batteries on average withstand 200-300 cycles down to 100% DoD (even that is often questionable) and 600-1100 cycles down to 50% DoD.

Although the initial price of the ExpertPower EP12100 is higher than the price of the equivalent 100Ah AGM battery, in the long run, ExpertPower EP12100 is more cost-effective.

ExpertPower EP12100: Connecting in Series or Parallel

According to the manufacturer, ExpertPower EP12100 is intended for 12V and 24V systems and it 'can' be connected in parallel to achieve larger capacities @12V and in series to achieve larger voltages @100Ah capacity.

But, connecting lithium-ion batteries in series and parallel depends on the features of the builtin BMS system, which can change over time.

At the moment of writing this article, according to the ExpertPower, it is necessary to fully charge a pair of ExpertPower EP12100 batteries separately (with the same models of battery chargers, preferably with the same charger) and only when they are fully charged, they should be connected in parallel or series.

Personally, this is a kind of complicated procedure - if You do need a lithium-ion battery that supports connecting in series and parallel, then go for Battle Born 12V 100Ah LiFePO4 Deep Cycle Battery (Amazon link, link opens in the new window), which is a slightly more expensive battery than ExpertPower EP12100.

ExpertPower EP12100 battery comes with a 1-year limited warranty.

ExpertPower EP12100 As a Trolling Motor Battery

ExpertPower EP12100 may be used as an excellent, lightweight trolling motor battery that can save a lot of weight when compared with the 100Ah AGM/Gel-Cell batteries and even provide more energy. This is very important for applications where battery weight may be of a great issue - kayak trolling motor battery.

With its maximum continuous discharge current of 70 Amps, ExpertPower EP12100 is able to power an electric trolling motor up to 55-60 lbs at full throttle for more than an hour and when the output thrust is decreased and the current is decreased down to, for example, 20 Amps, ExpertPower EP12100 is able to power such trolling motor for 5(!) hours.

Thanks to the maximum charging current of 50 Amps, ExpertPower EP12100 can be recharged very quickly.

ExpertPower EP12100 As an Inverter Battery

With its output voltage of 12.8 volts and up to 70 Amps, ExpertPower EP12100 may provide up to ~900 watts continuously.

Since most power inverters also support surge power which is often 2x normal power, ExpertPower EP12100 may provide up to 100 Amps for 10 seconds, which is ~1200-1250 watts.

With such surge output power and with a power inverter average efficiency of ~85%, ExpertPower EP12100 is suitable as an inverter battery for power inverters of up to ~1100 surge watts and ~550 nominal watts.

500 watts pure sine inverters are recommended power inverters that should be used with ExpertPower EP12100 - when the inverter is at full power (500W), a fully charged ExpertPower EP12100 battery may provide power up to two hours, with some energy still left in the battery.

ExpertPower EP12100 and 500W pure sine wave inverter may be used to power various home appliances during power outages when camping, and in other off-the-grid situations - at just a fraction weight of the lead-acid/power inverter combination.

ExpertPower EP12100 As a Wheelchair Battery

As a wheelchair battery, ExpertPower EP12100 provides great weight savings and more stable power output levels.

The wheelchairs with the total motor power of up to 700-800 watts and surge power up to 1200 watts can greatly benefit from the lithium-ion battery - just be sure to check the wheelchair battery charger and if it doesn't support the charging of the lithium batteries, remove it and replace with one that does support such batteries.

Other advantages of ExpertPower EP12100 as a wheelchair battery are a larger number of charging/discharging cycles and faster recharging.


expertpower ep12100 mLong Story Short: ExpertPower EP12100 initially costs more than lead-acid batteries, but it is maintenance-free, spill-proof battery that is much lighter, support a larger number of charging/discharging cycles, feature very flat output voltage curve, can be recharged quickly, has very low self-discharge rate, etc.

It can be used as an excellent lightweight trolling motor battery, wheelchair battery, inverter battery, RV battery and for all other off-the-grid applications where such battery is required.

ExpertPower EP12100 as a starting/cranking battery? No, it is simply not designed for such use.

For more reviews and recommendations, feel free to check ExpertPower EP12100 12V 100Ah Lithium LiFePO4 Deep Cycle Battery Amazon link (link opens in the new window).