Are lithium-ion batteries worth their price

Are lithium-ion batteries worth their price. This depends mostly on how and where you intend to use them. Here’s why. The lithium-ion batteries discussed here are LiFePO4 (their chemical make-up).

Lead acid and AGM batteries are bulky and heavy. Their size and weight, however, is rarely an issue for homes and properties. Most such batteries are fully charged daily. Lead acid batteries last longer if you discharge by only 20%. They may last 10-14 years so used. You can routinely discharge AGM batteries by 50%. They do, however, cost a third of lithium-ion batteries of similar nominal capacity.


This Fusion battery is claimed to drop-in replace existing deep-cycle batteries. Pic: Fusion.

Lithium-ion batteries – caravans & motorhomes

Caravans and motorhomes have differing priorities. Their space and weight they can carry is limited. Lead acid and AGM batteries are bulky and heavy. Both (12-volt) weigh over 30 kg per 100 amp hour. Users often routinely deeply discharge them. Furthermore, they rarely fully recharge them daily. Most such batteries last three/four years. AGM batteries last longer.

Lithium-ion batteries – energy and power

Energy is the ‘ability to perform work’. Amp hour capacity is a measure of that. Power relates to ‘how fast energy is releasable’. Here, promotion misleads. LiFePO4s can release huge power. A LiFePO4 may double as starter and deep cycle. However, in homes, such power is rarely, if ever, needed. It’s like a weight-lifter stacking supermarket shelves.

Where LiFePO4s score is an extended depth of discharge. Routinely discharged to 20% they withstand 2000 such cycles. They also output 13 volts-12.9 volts. This assists voltage sensitive equipment: e.g. fridges.

Lithium-ion Batteries – charging and monitoring

LiFePO4 batteries need specialist charging. They must have individual cell monitoring. This needs a battery management system. This is usually supplied with the battery. It may not be for ‘Ebay specials’.

Installing needs specialised knowledge. A few claim to be drop-in replacement products. These still need specific charging.

Are Lithium-ion Batteries Worth Their Price? – summary

Are lithium-ion batteries worth their price? A LiFePO4 costs three times more for similar capacity. This is offset by greater usable capacity.

LiFePO4 is a good buy for homes and properties. This is because the market is huge. LiFePO4 is also worthwhile where space and weight is an issue. For converted coaches, however, a large AGM battery bank will do the job at far less cost.

This is a complex topic. It can only be outlined in article form. Our book, Solar Success covers LiFePO4sfor homes and properties. Solar That Really Works! does likewise for cabins and RVs. Caravan & Motorhome Electrics covers all aspects.

All our books are now available in digital and print form. Digital versions are downloadable. (Click on the title/s). Print versions are available through all bookshops in Australia and New Zealand. Or via email from