Talk Morgan Forums Morgan Sports Cars Morgan Three Wheeler & Super 3 Replacement battery

I've just ordered a http://www.ebay.co.uk/itm/BATTERY-LITHIU...E-/191469157564

Will let you know how it goes in a week or two.

I have it on my Caterham. No problem at all.

The cold cranking amps (CCA) of a battery seems to be regarded as the more important parameter on this thread. This relates to the ability of the battery to supply enough current for the starter motor to turn the engine at adequate speed for it to start, and is temperature related. Whilst important this gives no indication of how long it can supply this current.

Its the capacity of the battery measured in amp hours (Ah) that should be considered of greater importance especially given that the engine may require several revolutions before firing. Furthermore any background load when car is not in use such as an immobiliser, will be better catered for by a battery of greater capacity than the puny 30 Ah original. Suggest a minimum of 40 Ah which will typically supply more than enough CCA.

Even an 850cc Moto Guzzi V twin motorbike had a 32 Ah battery as standard.

I'm not sure this is the right way round and for engine starting CCA is the key measure.

CCA is the maximum amps that can be continuously removed from a battery for 30 seconds at 0° before its voltage drops to unusable levels. So the standard 300 CCA battery can supply 300 amps for 30 seconds at 0°.

The Ah is a measure of capacity so the standard battery will supply 1 amp for 30 hours or 5 amps for 6 hours.

So more CCA = more power delivered to the starter motor with less voltage drop and hence easier starting.

CCA also improves as the temperature rises hence as I, and others, have experienced the starting is fine in summer but deteriorates as the temperature falls.

I had the same problem yesterday, i.e. cold morning resulting in thick oil and a 3 year old battery that was not really up to the job even when new.
The enging turned over a few times without firing and then the battery was drained to the point where it would not turn the engine over any more. This is despite being hooked to a C-TEK maintenance charger all the time it is in the garage. I connected a conventional charger to the battery and after 4 hours it span the engine over and it started easily.
I also think the question of the limited CCA capacity of the standard battery is the crucial factor and I wonder if anybody has considered fitting a second battery (of the same type as the original) and connecting it with heavy cables, in parellel with the existing battery, to effectively provide a total CCA of 600 Amps.
I think there is room under the bonnet on the passenger side to fit a second battery tray and the associated battery retaining strap and I have just been quoted £48.00 for a replacement battery so replacing the pair in the future would only cost around £100 and they combined would give the greater CCA needed.
I would welcome other member's thoughts on this.

The Westco battery I have fitted has CCA of 400A and whilst it did not start instantly this morning did start quite easily. This battery is essentially the same dimensions as the Banner battery. However there is plenty of space above the battery so a wider battery could be accommodated by positioning it higher than the existing, this gives many more options for choosing a battery with greater capacity. I did not go this route because I thought the Westco would be direct swop but as it turned out was a few millimetres wider and required an adaptor making anyway.