I store my NaBH4 in 250 g plastic containers (do NOT use glass!)
Why is it necesary to use plastic containers? My borohydride is packed in glass bottles by manufacturer.
http://physchem.ox.ac.uk/MSDS/SO/sodium_borohydride.html (http://physchem.ox.ac.uk/MSDS/SO/sodium_borohydride.html)