Why Are People So Down On Gel Batteries?

[AngusMcDoon]

If you tried using you mobile phone battery from 10 years ago to run your mobile phone today, it'd last perhaps an hour.

Sony Ericsson P800, 2002 vintage, standard battery BST-15, 3.6V, Li-Po, 1000mAh.

Samsung Galaxy S2, 2012 vintage, standard battery 3.6V, Li-ion, 1000mAh.

Absolutely no difference. Methinks you know not what about you talk.

[sailinglegend420]

.... I downloaded a spreadsheet that allows comparison of battery types. After entering my own power usage data it appeared to support purchase of AGMs. However, when I updated the actual UK purchase costs for AGM & T105s the picture changed completely.

To make the real comparison of AGMs versus flooded you must include the costs savings from the reduced engine or generator running costs. See pages 4-6 here:

http://www.vonwentzel.net/Battery/04.Costs/index.html

Lifeline AGMs come out as cheapest, but the I suppose you can prove anything with figures if you want to.

[Mistroma]

To make the real comparison of AGMs versus flooded you must include the costs savings from the reduced engine or generator running costs. See pages 4-6 here:

http://www.vonwentzel.net/Battery/04.Costs/index.html

Lifeline AGMs come out as cheapest, but the I suppose you can prove anything with figures if you want to.

Graphs on link look exactly like ones on the spreadsheet I downloaded. Key point for me was that the costs were miles out for UK prices I could get. I entered data for power usage, battery prices and all other relevant data. The result persuaded me to go for T105s.

I did say that everyone had different usage patterns and mine probably suit T105s. I have records of engine hours, wind-gen output etc. for last few years. I would need to check but am pretty certain that I only ran the engine for 2-3 hours just for charging in 2011. I didn't count the cost of running the engine when actually travelling. I assumed that any difference in fuel cost was minimal when using the engine for propulsion. i.e. Fuel usage to charge AGM or flooded aren't significant when motoring at 7 knots. Could be wrong of course.

I suspect that many people use this spreadsheet without updating all the relevant data (including battery prices).

[bjvarley]

The battery question is difficult but we have used standard (so called sealed) lead acid batteries for two years now .. deep cycled often.. if you take the plastic label off the top you will probably find regular filling plugs underneath . Ours needed about 1.5 Ltrs of distilled water after a year of use (not exactly maintenance free !)

[canalcruiser]

I bought two gel batteries in 2005,second hand,from an electric car.One lasted a few months and died.The other is still in perfect condition,not just consinged to running the bilge pump but for the last two years its a lighting and bilge dedicated battery charged with an 18w solar panel

12.92v as of this moment