Below is an article by Flashbattery, which looks at the advantages of Lithium Ion batteries compared to lead acid batteries used on forklift trucks. To be fair, Lucas have developed a special lead acid battery which overcomes some of these deficiencies. The article is arranged in the form of headlines and the writer suggests they could write a book on the subject!
Charging the battery
Lead Acid battery: The charging efficiency of this type of battery is low – only 70%! A lead-acid battery needs more energy for recharging than it delivers. The excess energy is used for gasification and for mixing the acid internally. This process warms up the battery and evaporates the water inside, which results in the need to top up the battery with distilled (demineralised) water. Lead-acid recharging has severe limitations and a number of critical points. Here are the most important ones:
Lithium ion battery: Lithium-ion batteries can be “fast” charged to 100% of capacity.
A lithium battery saves on your electric bill, as it is up to 96% efficient and accepts both partial and rapid charging.
A lithium battery can be charged to 50% capacity in only 30 minutes. This innovative characteristic enables our customers to equip their devices with lower installed battery capacity than the capacity required with lead-acid batteries, because lithium batteries can be recharged repeatedly over a short time.
Electronic systems inside the battery control the charger effectively, so it can deliver the exact current that is consistent with internal parameters (voltage, temperature, charge level, etc …). If a customer connects an unsuitable battery charger, the battery will not activate and is thus fully protected.
Lead Acid battery: 30Kg for kWh. Lithium ion battery: 9Kg for kWh
On average Lithium-Ion batteries weight 3 times less than standard lead acid battery.
(Webmaste'r note). Bear in mind the battery weight forms an important part of the counterbalancing on an electric forklift truck and such forklifts have a MINIMUM battery weight in their specifications. It’s important that professional advice is taken before simply changing to Lithium Iron.
Lead acid battery: High maintenance and systems costs. Ordinary maintenance is one of the greatest costs, as it includes topping up the water, maintaining the filling system, and removing oxide from the elements and terminals. It would be a serious mistake not to take into consideration 3 other, hidden costs:
Lithium ion battery: no infrastructure cost, no gas and no need for water, which eliminates all additional costs. The battery just works.
Lithium-ion batteries last 3-4 times longer than lead-acid batteries, without losing effectiveness over time.
Safety, waterproofing and emissions
Lead acid batteries have no safety devices, are not sealed, and release hydrogen during charging. In fact, their use in the food industry is not permitted (except for “gel” versions, which are even less efficient).
Lithium batteries release no emissions, are suitable for all applications (also available in IP67) and feature 3 different control systems that protect the battery:
One final point. I looked on line at prices and found a 13.2 volt Lithium Ion Traction battery for £2229 and a 48 volt Lead Acid battery for £1629. Not a fair comparison I know but it does suggest a huge price difference like for like.